diff --git a/src/pocketmine/Player.php b/src/pocketmine/Player.php
index ee9ff70e4..787ba7054 100644
--- a/src/pocketmine/Player.php
+++ b/src/pocketmine/Player.php
@@ -401,7 +401,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 	 *
 	 * @return UUID|null
 	 */
-	public function getUniqueId(){
+	public function getUniqueId() : ?UUID{
 		return parent::getUniqueId();
 	}
 
@@ -459,7 +459,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 	/**
 	 * @param Player $player
 	 */
-	public function spawnTo(Player $player){
+	public function spawnTo(Player $player) : void{
 		if($this->spawned and $player->spawned and $this->isAlive() and $player->isAlive() and $player->getLevel() === $this->level and $player->canSee($this) and !$this->isSpectator()){
 			parent::spawnTo($player);
 		}
@@ -538,7 +538,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		return !$this->isSpectator();
 	}
 
-	public function resetFallDistance(){
+	public function resetFallDistance() : void{
 		parent::resetFallDistance();
 		if($this->inAirTicks !== 0){
 			$this->startAirTicks = 5;
@@ -812,7 +812,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 	 *
 	 * If null is given, will additionally send the skin to the player itself as well as its viewers.
 	 */
-	public function sendSkin(array $targets = null) : void{
+	public function sendSkin(?array $targets = null) : void{
 		parent::sendSkin($targets ?? $this->server->getOnlinePlayers());
 	}
 
@@ -1487,7 +1487,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		return 0;
 	}
 
-	protected function checkGroundState(float $movX, float $movY, float $movZ, float $dx, float $dy, float $dz){
+	protected function checkGroundState(float $movX, float $movY, float $movZ, float $dx, float $dy, float $dz) : void{
 		if(!$this->onGround or $movY != 0){
 			$bb = clone $this->boundingBox;
 			$bb->minY = $this->y - 0.2;
@@ -1637,13 +1637,13 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		$this->newPosition = null;
 	}
 
-	public function jump(){
+	public function jump() : void{
 		$this->server->getPluginManager()->callEvent(new PlayerJumpEvent($this));
 		parent::jump();
 	}
 
-	public function setMotion(Vector3 $mot){
-		if(parent::setMotion($mot)){
+	public function setMotion(Vector3 $motion) : bool{
+		if(parent::setMotion($motion)){
 			$this->broadcastMotion();
 
 			if($this->motionY > 0){
@@ -1655,11 +1655,11 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		return false;
 	}
 
-	protected function updateMovement(bool $teleport = false){
+	protected function updateMovement(bool $teleport = false) : void{
 
 	}
 
-	protected function tryChangeMovement(){
+	protected function tryChangeMovement() : void{
 
 	}
 
@@ -1744,7 +1744,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		return true;
 	}
 
-	public function doFoodTick(int $tickDiff = 1){
+	public function doFoodTick(int $tickDiff = 1) : void{
 		if($this->isSurvival()){
 			parent::doFoodTick($tickDiff);
 		}
@@ -1827,11 +1827,11 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		return ($targetDot - $eyeDot) >= -$maxDiff;
 	}
 
-	protected function initHumanData(){
+	protected function initHumanData() : void{
 		$this->setNameTag($this->username);
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 		$this->addDefaultWindows();
 	}
@@ -3340,7 +3340,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 	 * @param string               $reason Reason showed in console
 	 * @param bool                 $notify
 	 */
-	final public function close($message = "", string $reason = "generic reason", bool $notify = true){
+	final public function close($message = "", string $reason = "generic reason", bool $notify = true) : void{
 		if($this->isConnected() and !$this->closed){
 
 			try{
@@ -3491,7 +3491,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		}
 	}
 
-	public function kill(){
+	public function kill() : void{
 		if(!$this->spawned){
 			return;
 		}
@@ -3501,7 +3501,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		$this->sendRespawnPacket($this->getSpawn());
 	}
 
-	protected function onDeath(){
+	protected function onDeath() : void{
 		$message = "death.attack.generic";
 
 		$params = [
@@ -3689,7 +3689,7 @@ class Player extends Human implements CommandSender, ChunkLoader, IPlayer{
 		$this->exhaust(0.3, PlayerExhaustEvent::CAUSE_DAMAGE);
 	}
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		if(!$this->isAlive()){
 			return;
 		}
diff --git a/src/pocketmine/entity/Attribute.php b/src/pocketmine/entity/Attribute.php
index 3a7284e00..835a2debe 100644
--- a/src/pocketmine/entity/Attribute.php
+++ b/src/pocketmine/entity/Attribute.php
@@ -51,7 +51,7 @@ class Attribute{
 	/** @var Attribute[] */
 	protected static $attributes = [];
 
-	public static function init(){
+	public static function init() : void{
 		self::addAttribute(self::ABSORPTION, "minecraft:absorption", 0.00, 340282346638528859811704183484516925440.00, 0.00);
 		self::addAttribute(self::SATURATION, "minecraft:player.saturation", 0.00, 20.00, 20.00);
 		self::addAttribute(self::EXHAUSTION, "minecraft:player.exhaustion", 0.00, 5.00, 0.0);
@@ -92,7 +92,7 @@ class Attribute{
 	 *
 	 * @return Attribute|null
 	 */
-	public static function getAttribute(int $id){
+	public static function getAttribute(int $id) : ?Attribute{
 		return isset(self::$attributes[$id]) ? clone self::$attributes[$id] : null;
 	}
 
@@ -101,7 +101,7 @@ class Attribute{
 	 *
 	 * @return Attribute|null
 	 */
-	public static function getAttributeByName(string $name){
+	public static function getAttributeByName(string $name) : ?Attribute{
 		foreach(self::$attributes as $a){
 			if($a->getName() === $name){
 				return clone $a;
@@ -170,7 +170,7 @@ class Attribute{
 		return $this;
 	}
 
-	public function resetToDefault(){
+	public function resetToDefault() : void{
 		$this->setValue($this->getDefaultValue());
 	}
 
@@ -219,7 +219,7 @@ class Attribute{
 		return $this->shouldSend and $this->desynchronized;
 	}
 
-	public function markSynchronized(bool $synced = true){
+	public function markSynchronized(bool $synced = true) : void{
 		$this->desynchronized = !$synced;
 	}
 }
diff --git a/src/pocketmine/entity/AttributeMap.php b/src/pocketmine/entity/AttributeMap.php
index 1c1c85276..dd07a8619 100644
--- a/src/pocketmine/entity/AttributeMap.php
+++ b/src/pocketmine/entity/AttributeMap.php
@@ -27,7 +27,7 @@ class AttributeMap implements \ArrayAccess{
 	/** @var Attribute[] */
 	private $attributes = [];
 
-	public function addAttribute(Attribute $attribute){
+	public function addAttribute(Attribute $attribute) : void{
 		$this->attributes[$attribute->getId()] = $attribute;
 	}
 
@@ -36,7 +36,7 @@ class AttributeMap implements \ArrayAccess{
 	 *
 	 * @return Attribute|null
 	 */
-	public function getAttribute(int $id){
+	public function getAttribute(int $id) : ?Attribute{
 		return $this->attributes[$id] ?? null;
 	}
 
@@ -56,19 +56,28 @@ class AttributeMap implements \ArrayAccess{
 		});
 	}
 
-	public function offsetExists($offset){
+	public function offsetExists($offset) : bool{
 		return isset($this->attributes[$offset]);
 	}
 
-	public function offsetGet($offset){
+	/**
+	 * @param int $offset
+	 *
+	 * @return float
+	 */
+	public function offsetGet($offset) : float{
 		return $this->attributes[$offset]->getValue();
 	}
 
-	public function offsetSet($offset, $value){
+	/**
+	 * @param int   $offset
+	 * @param float $value
+	 */
+	public function offsetSet($offset, $value) : void{
 		$this->attributes[$offset]->setValue($value);
 	}
 
-	public function offsetUnset($offset){
+	public function offsetUnset($offset) : void{
 		throw new \RuntimeException("Could not unset an attribute from an attribute map");
 	}
 }
diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index 24ef8b515..fbfa531e3 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/src/pocketmine/entity/Entity.php
@@ -573,7 +573,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @return string
 	 */
-	public function getNameTag(){
+	public function getNameTag() : string{
 		return $this->propertyManager->getString(self::DATA_NAMETAG);
 	}
 
@@ -595,21 +595,21 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @param string $name
 	 */
-	public function setNameTag($name){
+	public function setNameTag(string $name) : void{
 		$this->propertyManager->setString(self::DATA_NAMETAG, $name);
 	}
 
 	/**
 	 * @param bool $value
 	 */
-	public function setNameTagVisible(bool $value = true){
+	public function setNameTagVisible(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_CAN_SHOW_NAMETAG, $value);
 	}
 
 	/**
 	 * @param bool $value
 	 */
-	public function setNameTagAlwaysVisible(bool $value = true){
+	public function setNameTagAlwaysVisible(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_ALWAYS_SHOW_NAMETAG, $value);
 	}
 
@@ -623,7 +623,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @param float $value
 	 */
-	public function setScale(float $value){
+	public function setScale(float $value) : void{
 		$multiplier = $value / $this->getScale();
 
 		$this->width *= $multiplier;
@@ -635,7 +635,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$this->propertyManager->setFloat(self::DATA_SCALE, $value);
 	}
 
-	public function getBoundingBox(){
+	public function getBoundingBox() : AxisAlignedBB{
 		return $this->boundingBox;
 	}
 
@@ -656,7 +656,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->getGenericFlag(self::DATA_FLAG_SNEAKING);
 	}
 
-	public function setSneaking(bool $value = true){
+	public function setSneaking(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_SNEAKING, $value);
 	}
 
@@ -664,7 +664,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->getGenericFlag(self::DATA_FLAG_SPRINTING);
 	}
 
-	public function setSprinting(bool $value = true){
+	public function setSprinting(bool $value = true) : void{
 		if($value !== $this->isSprinting()){
 			$this->setGenericFlag(self::DATA_FLAG_SPRINTING, $value);
 			$attr = $this->attributeMap->getAttribute(Attribute::MOVEMENT_SPEED);
@@ -676,7 +676,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->getGenericFlag(self::DATA_FLAG_IMMOBILE);
 	}
 
-	public function setImmobile(bool $value = true){
+	public function setImmobile(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_IMMOBILE, $value);
 	}
 
@@ -698,9 +698,10 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 
 	/**
 	 * Sets whether the entity is able to climb climbable blocks.
+	 *
 	 * @param bool $value
 	 */
-	public function setCanClimb(bool $value = true){
+	public function setCanClimb(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_CAN_CLIMB, $value);
 	}
 
@@ -718,7 +719,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @param bool $value
 	 */
-	public function setCanClimbWalls(bool $value = true){
+	public function setCanClimbWalls(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_WALLCLIMBING, $value);
 	}
 
@@ -726,7 +727,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * Returns the entity ID of the owning entity, or null if the entity doesn't have an owner.
 	 * @return int|null
 	 */
-	public function getOwningEntityId(){
+	public function getOwningEntityId() : ?int{
 		return $this->propertyManager->getLong(self::DATA_OWNER_EID);
 	}
 
@@ -734,7 +735,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * Returns the owning entity, or null if the entity was not found.
 	 * @return Entity|null
 	 */
-	public function getOwningEntity(){
+	public function getOwningEntity() : ?Entity{
 		$eid = $this->getOwningEntityId();
 		if($eid !== null){
 			return $this->server->findEntity($eid, $this->level);
@@ -750,7 +751,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @throws \InvalidArgumentException if the supplied entity is not valid
 	 */
-	public function setOwningEntity(Entity $owner = null){
+	public function setOwningEntity(?Entity $owner) : void{
 		if($owner === null){
 			$this->propertyManager->removeProperty(self::DATA_OWNER_EID);
 		}elseif($owner->closed){
@@ -764,7 +765,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * Returns the entity ID of the entity's target, or null if it doesn't have a target.
 	 * @return int|null
 	 */
-	public function getTargetEntityId(){
+	public function getTargetEntityId() : ?int{
 		return $this->propertyManager->getLong(self::DATA_TARGET_EID);
 	}
 
@@ -774,7 +775,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @return Entity|null
 	 */
-	public function getTargetEntity(){
+	public function getTargetEntity() : ?Entity{
 		$eid = $this->getTargetEntityId();
 		if($eid !== null){
 			return $this->server->findEntity($eid, $this->level);
@@ -790,7 +791,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @throws \InvalidArgumentException if the target entity is not valid
 	 */
-	public function setTargetEntity(Entity $target = null){
+	public function setTargetEntity(?Entity $target) : void{
 		if($target === null){
 			$this->propertyManager->removeProperty(self::DATA_TARGET_EID);
 		}elseif($target->closed){
@@ -823,7 +824,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @return string
 	 */
-	public function getSaveId(){
+	public function getSaveId() : string{
 		if(!isset(self::$saveNames[static::class])){
 			throw new \InvalidStateException("Entity is not registered");
 		}
@@ -831,7 +832,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return current(self::$saveNames[static::class]);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		if(!($this instanceof Player)){
 			$this->namedtag->setString("id", $this->getSaveId(), true);
 
@@ -867,7 +868,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$this->namedtag->setByte("Invulnerable", $this->invulnerable ? 1 : 0);
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		assert($this->namedtag instanceof CompoundTag);
 
 		if($this->namedtag->hasTag("CustomName", StringTag::class)){
@@ -885,14 +886,14 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$this->scheduleUpdate();
 	}
 
-	protected function addAttributes(){
+	protected function addAttributes() : void{
 
 	}
 
 	/**
 	 * @param EntityDamageEvent $source
 	 */
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		$this->server->getPluginManager()->callEvent($source);
 		if($source->isCancelled()){
 			return;
@@ -906,7 +907,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @param EntityRegainHealthEvent $source
 	 */
-	public function heal(EntityRegainHealthEvent $source){
+	public function heal(EntityRegainHealthEvent $source) : void{
 		$this->server->getPluginManager()->callEvent($source);
 		if($source->isCancelled()){
 			return;
@@ -915,7 +916,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$this->setHealth($this->getHealth() + $source->getAmount());
 	}
 
-	public function kill(){
+	public function kill() : void{
 		$this->health = 0;
 		$this->scheduleUpdate();
 	}
@@ -946,7 +947,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @param float $amount
 	 */
-	public function setHealth(float $amount){
+	public function setHealth(float $amount) : void{
 		if($amount == $this->health){
 			return;
 		}
@@ -973,25 +974,25 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @param int $amount
 	 */
-	public function setMaxHealth(int $amount){
+	public function setMaxHealth(int $amount) : void{
 		$this->maxHealth = $amount;
 	}
 
 	/**
 	 * @param EntityDamageEvent $type
 	 */
-	public function setLastDamageCause(EntityDamageEvent $type){
+	public function setLastDamageCause(EntityDamageEvent $type) : void{
 		$this->lastDamageCause = $type;
 	}
 
 	/**
 	 * @return EntityDamageEvent|null
 	 */
-	public function getLastDamageCause(){
+	public function getLastDamageCause() : ?EntityDamageEvent{
 		return $this->lastDamageCause;
 	}
 
-	public function getAttributeMap(){
+	public function getAttributeMap() : AttributeMap{
 		return $this->attributeMap;
 	}
 
@@ -1041,7 +1042,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->fireTicks > 0;
 	}
 
-	public function setOnFire(int $seconds){
+	public function setOnFire(int $seconds) : void{
 		$ticks = $seconds * 20;
 		if($ticks > $this->fireTicks){
 			$this->fireTicks = $ticks;
@@ -1064,7 +1065,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		$this->fireTicks = $fireTicks;
 	}
 
-	public function extinguish(){
+	public function extinguish() : void{
 		$this->fireTicks = 0;
 		$this->setGenericFlag(self::DATA_FLAG_ONFIRE, false);
 	}
@@ -1096,7 +1097,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * Called to deal damage to entities when they are on fire.
 	 */
-	protected function dealFireDamage(){
+	protected function dealFireDamage() : void{
 		$ev = new EntityDamageEvent($this, EntityDamageEvent::CAUSE_FIRE_TICK, 1);
 		$this->attack($ev);
 	}
@@ -1109,7 +1110,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return true;
 	}
 
-	protected function updateMovement(bool $teleport = false){
+	protected function updateMovement(bool $teleport = false) : void{
 		$diffPosition = ($this->x - $this->lastX) ** 2 + ($this->y - $this->lastY) ** 2 + ($this->z - $this->lastZ) ** 2;
 		$diffRotation = ($this->yaw - $this->lastYaw) ** 2 + ($this->pitch - $this->lastPitch) ** 2;
 
@@ -1139,7 +1140,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return new Vector3($vector3->x, $vector3->y + $this->baseOffset, $vector3->z);
 	}
 
-	protected function broadcastMovement(bool $teleport = false){
+	protected function broadcastMovement(bool $teleport = false) : void{
 		if($this->chunk !== null){
 			$pk = new MoveEntityPacket();
 			$pk->entityRuntimeId = $this->id;
@@ -1153,7 +1154,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		}
 	}
 
-	protected function broadcastMotion(){
+	protected function broadcastMotion() : void{
 		if($this->chunk !== null){
 			$pk = new SetEntityMotionPacket();
 			$pk->entityRuntimeId = $this->id;
@@ -1167,11 +1168,11 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return false;
 	}
 
-	protected function applyGravity(){
+	protected function applyGravity() : void{
 		$this->motionY -= $this->gravity;
 	}
 
-	protected function tryChangeMovement(){
+	protected function tryChangeMovement() : void{
 		$friction = 1 - $this->drag;
 
 		if($this->applyDragBeforeGravity()){
@@ -1290,7 +1291,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @return int|null
 	 */
-	public function getDirection(){
+	public function getDirection() : ?int{
 		$rotation = ($this->yaw - 90) % 360;
 		if($rotation < 0){
 			$rotation += 360.0;
@@ -1388,7 +1389,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		//return !($this instanceof Player);
 	}
 
-	final public function scheduleUpdate(){
+	final public function scheduleUpdate() : void{
 		$this->level->updateEntities[$this->id] = $this;
 	}
 
@@ -1403,7 +1404,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @param bool $value
 	 */
-	final public function setForceMovementUpdate(bool $value = true){
+	final public function setForceMovementUpdate(bool $value = true) : void{
 		$this->forceMovementUpdate = $value;
 
 		$this->blocksAround = null;
@@ -1427,7 +1428,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return true;
 	}
 
-	public function resetFallDistance(){
+	public function resetFallDistance() : void{
 		$this->fallDistance = 0.0;
 	}
 
@@ -1435,7 +1436,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @param float $distanceThisTick
 	 * @param bool  $onGround
 	 */
-	protected function updateFallState(float $distanceThisTick, bool $onGround){
+	protected function updateFallState(float $distanceThisTick, bool $onGround) : void{
 		if($onGround){
 			if($this->fallDistance > 0){
 				$this->fall($this->fallDistance);
@@ -1451,7 +1452,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @param float $fallDistance
 	 */
-	public function fall(float $fallDistance){
+	public function fall(float $fallDistance) : void{
 
 	}
 
@@ -1459,7 +1460,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return $this->eyeHeight;
 	}
 
-	public function onCollideWithPlayer(Player $player){
+	public function onCollideWithPlayer(Player $player) : void{
 
 	}
 
@@ -1669,7 +1670,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		Timings::$entityMoveTimer->stopTiming();
 	}
 
-	protected function checkGroundState(float $movX, float $movY, float $movZ, float $dx, float $dy, float $dz){
+	protected function checkGroundState(float $movX, float $movY, float $movZ, float $dx, float $dy, float $dz) : void{
 		$this->isCollidedVertically = $movY != $dy;
 		$this->isCollidedHorizontally = ($movX != $dx or $movZ != $dz);
 		$this->isCollided = ($this->isCollidedHorizontally or $this->isCollidedVertically);
@@ -1716,7 +1717,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return true;
 	}
 
-	protected function checkBlockCollision(){
+	protected function checkBlockCollision() : void{
 		$vector = $this->temporalVector->setComponents(0, 0, 0);
 
 		foreach($this->getBlocksAround() as $block){
@@ -1765,7 +1766,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return true;
 	}
 
-	public function setRotation(float $yaw, float $pitch){
+	public function setRotation(float $yaw, float $pitch) : void{
 		$this->yaw = $yaw;
 		$this->pitch = $pitch;
 		$this->scheduleUpdate();
@@ -1781,7 +1782,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return false;
 	}
 
-	protected function checkChunks(){
+	protected function checkChunks() : void{
 		$chunkX = $this->getFloorX() >> 4;
 		$chunkZ = $this->getFloorZ() >> 4;
 		if($this->chunk === null or ($this->chunk->getX() !== $chunkX or $this->chunk->getZ() !== $chunkZ)){
@@ -1812,7 +1813,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		}
 	}
 
-	protected function resetLastMovements(){
+	protected function resetLastMovements() : void{
 		list($this->lastX, $this->lastY, $this->lastZ) = [$this->x, $this->y, $this->z];
 		list($this->lastYaw, $this->lastPitch) = [$this->yaw, $this->pitch];
 		list($this->lastMotionX, $this->lastMotionY, $this->lastMotionZ) = [$this->motionX, $this->motionY, $this->motionZ];
@@ -1822,7 +1823,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		return new Vector3($this->motionX, $this->motionY, $this->motionZ);
 	}
 
-	public function setMotion(Vector3 $motion){
+	public function setMotion(Vector3 $motion) : bool{
 		if(!$this->justCreated){
 			$this->server->getPluginManager()->callEvent($ev = new EntityMotionEvent($this, $motion));
 			if($ev->isCancelled()){
@@ -1852,7 +1853,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * @return bool
 	 */
-	public function teleport(Vector3 $pos, float $yaw = null, float $pitch = null) : bool{
+	public function teleport(Vector3 $pos, ?float $yaw = null, ?float $pitch = null) : bool{
 		if($pos instanceof Location){
 			$yaw = $yaw ?? $pos->yaw;
 			$pitch = $pitch ?? $pos->pitch;
@@ -1937,7 +1938,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	/**
 	 * @param Player $player
 	 */
-	public function spawnTo(Player $player){
+	public function spawnTo(Player $player) : void{
 		if(!isset($this->hasSpawned[$player->getLoaderId()]) and $this->chunk !== null and isset($player->usedChunks[Level::chunkHash($this->chunk->getX(), $this->chunk->getZ())])){
 			$this->hasSpawned[$player->getLoaderId()] = $player;
 
@@ -1945,7 +1946,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		}
 	}
 
-	public function spawnToAll(){
+	public function spawnToAll() : void{
 		if($this->chunk === null or $this->closed){
 			return;
 		}
@@ -1956,7 +1957,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		}
 	}
 
-	public function respawnToAll(){
+	public function respawnToAll() : void{
 		foreach($this->hasSpawned as $key => $player){
 			unset($this->hasSpawned[$key]);
 			$this->spawnTo($player);
@@ -1967,7 +1968,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @param Player $player
 	 * @param bool   $send
 	 */
-	public function despawnFrom(Player $player, bool $send = true){
+	public function despawnFrom(Player $player, bool $send = true) : void{
 		if(isset($this->hasSpawned[$player->getLoaderId()])){
 			if($send){
 				$pk = new RemoveEntityPacket();
@@ -1978,7 +1979,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 		}
 	}
 
-	public function despawnFromAll(){
+	public function despawnFromAll() : void{
 		foreach($this->hasSpawned as $player){
 			$this->despawnFrom($player);
 		}
@@ -2008,7 +2009,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 *
 	 * WARNING: Entities are unusable after this has been executed!
 	 */
-	public function close(){
+	public function close() : void{
 		if(!$this->closed){
 			$this->server->getPluginManager()->callEvent(new EntityDespawnEvent($this));
 			$this->closed = true;
@@ -2037,7 +2038,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @param bool $value
 	 * @param int  $propertyType
 	 */
-	public function setDataFlag(int $propertyId, int $flagId, bool $value = true, int $propertyType = self::DATA_TYPE_LONG){
+	public function setDataFlag(int $propertyId, int $flagId, bool $value = true, int $propertyType = self::DATA_TYPE_LONG) : void{
 		if($this->getDataFlag($propertyId, $flagId) !== $value){
 			$flags = (int) $this->propertyManager->getPropertyValue($propertyId, $propertyType);
 			$flags ^= 1 << $flagId;
@@ -2071,7 +2072,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @param int  $flagId
 	 * @param bool $value
 	 */
-	public function setGenericFlag(int $flagId, bool $value = true){
+	public function setGenericFlag(int $flagId, bool $value = true) : void{
 		$this->setDataFlag(self::DATA_FLAGS, $flagId, $value, self::DATA_TYPE_LONG);
 	}
 
@@ -2079,7 +2080,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	 * @param Player[]|Player $player
 	 * @param array           $data Properly formatted entity data, defaults to everything
 	 */
-	public function sendData($player, array $data = null){
+	public function sendData($player, ?array $data = null) : void{
 		if(!is_array($player)){
 			$player = [$player];
 		}
diff --git a/src/pocketmine/entity/Human.php b/src/pocketmine/entity/Human.php
index 2fd9d71f0..44e965eea 100644
--- a/src/pocketmine/entity/Human.php
+++ b/src/pocketmine/entity/Human.php
@@ -111,7 +111,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	/**
 	 * @return UUID|null
 	 */
-	public function getUniqueId(){
+	public function getUniqueId() : ?UUID{
 		return $this->uuid;
 	}
 
@@ -151,14 +151,14 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	 *
 	 * @param Player[]|null $targets
 	 */
-	public function sendSkin(array $targets = null) : void{
+	public function sendSkin(?array $targets = null) : void{
 		$pk = new PlayerSkinPacket();
 		$pk->uuid = $this->getUniqueId();
 		$pk->skin = $this->skin;
 		$this->server->broadcastPacket($targets ?? $this->hasSpawned, $pk);
 	}
 
-	public function jump(){
+	public function jump() : void{
 		parent::jump();
 		if($this->isSprinting()){
 			$this->exhaust(0.8, PlayerExhaustEvent::CAUSE_SPRINT_JUMPING);
@@ -179,7 +179,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	 *
 	 * @throws \InvalidArgumentException
 	 */
-	public function setFood(float $new){
+	public function setFood(float $new) : void{
 		$attr = $this->attributeMap->getAttribute(Attribute::HUNGER);
 		$old = $attr->getValue();
 		$attr->setValue($new);
@@ -202,7 +202,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		return $this->attributeMap->getAttribute(Attribute::HUNGER)->getMaxValue();
 	}
 
-	public function addFood(float $amount){
+	public function addFood(float $amount) : void{
 		$attr = $this->attributeMap->getAttribute(Attribute::HUNGER);
 		$amount += $attr->getValue();
 		$amount = max(min($amount, $attr->getMaxValue()), $attr->getMinValue());
@@ -230,11 +230,11 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	 *
 	 * @throws \InvalidArgumentException
 	 */
-	public function setSaturation(float $saturation){
+	public function setSaturation(float $saturation) : void{
 		$this->attributeMap->getAttribute(Attribute::SATURATION)->setValue($saturation);
 	}
 
-	public function addSaturation(float $amount){
+	public function addSaturation(float $amount) : void{
 		$attr = $this->attributeMap->getAttribute(Attribute::SATURATION);
 		$attr->setValue($attr->getValue() + $amount, true);
 	}
@@ -249,7 +249,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	 *
 	 * @param float $exhaustion
 	 */
-	public function setExhaustion(float $exhaustion){
+	public function setExhaustion(float $exhaustion) : void{
 		$this->attributeMap->getAttribute(Attribute::EXHAUSTION)->setValue($exhaustion);
 	}
 
@@ -529,14 +529,14 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		return $this->inventory;
 	}
 
-	public function getEnderChestInventory(){
+	public function getEnderChestInventory() : EnderChestInventory{
 		return $this->enderChestInventory;
 	}
 
 	/**
 	 * For Human entities which are not players, sets their properties such as nametag, skin and UUID from NBT.
 	 */
-	protected function initHumanData(){
+	protected function initHumanData() : void{
 		if($this->namedtag->hasTag("NameTag", StringTag::class)){
 			$this->setNameTag($this->namedtag->getString("NameTag"));
 		}
@@ -555,7 +555,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		$this->uuid = UUID::fromData((string) $this->getId(), $this->skin->getSkinData(), $this->getNameTag());
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->setPlayerFlag(self::DATA_PLAYER_FLAG_SLEEP, false);
@@ -607,7 +607,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		}
 	}
 
-	protected function addAttributes(){
+	protected function addAttributes() : void{
 		parent::addAttributes();
 
 		$this->attributeMap->addAttribute(Attribute::getAttribute(Attribute::SATURATION));
@@ -629,7 +629,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		return $hasUpdate;
 	}
 
-	public function doFoodTick(int $tickDiff = 1){
+	public function doFoodTick(int $tickDiff = 1) : void{
 		if($this->isAlive()){
 			$food = $this->getFood();
 			$health = $this->getHealth();
@@ -681,7 +681,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 
 		$this->namedtag->setInt("foodLevel", (int) $this->getFood(), true);
@@ -743,7 +743,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		}
 	}
 
-	public function spawnTo(Player $player){
+	public function spawnTo(Player $player) : void{
 		if($player !== $this){
 			parent::spawnTo($player);
 		}
@@ -776,7 +776,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		}
 	}
 
-	public function close(){
+	public function close() : void{
 		if(!$this->closed){
 			if($this->inventory !== null){
 				$this->inventory->removeAllViewers(true);
@@ -806,7 +806,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	 * @param int  $flagId
 	 * @param bool $value
 	 */
-	public function setPlayerFlag(int $flagId, bool $value = true){
+	public function setPlayerFlag(int $flagId, bool $value = true) : void{
 		$this->setDataFlag(self::DATA_PLAYER_FLAGS, $flagId, $value, self::DATA_TYPE_BYTE);
 	}
 }
diff --git a/src/pocketmine/entity/Living.php b/src/pocketmine/entity/Living.php
index 948fb19d6..be4c56237 100644
--- a/src/pocketmine/entity/Living.php
+++ b/src/pocketmine/entity/Living.php
@@ -72,7 +72,7 @@ abstract class Living extends Entity implements Damageable{
 
 	abstract public function getName() : string;
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->armorInventory = new ArmorInventory($this);
@@ -112,7 +112,7 @@ abstract class Living extends Entity implements Damageable{
 		}
 	}
 
-	protected function addAttributes(){
+	protected function addAttributes() : void{
 		$this->attributeMap->addAttribute(Attribute::getAttribute(Attribute::HEALTH));
 		$this->attributeMap->addAttribute(Attribute::getAttribute(Attribute::FOLLOW_RANGE));
 		$this->attributeMap->addAttribute(Attribute::getAttribute(Attribute::KNOCKBACK_RESISTANCE));
@@ -121,7 +121,7 @@ abstract class Living extends Entity implements Damageable{
 		$this->attributeMap->addAttribute(Attribute::getAttribute(Attribute::ABSORPTION));
 	}
 
-	public function setHealth(float $amount){
+	public function setHealth(float $amount) : void{
 		$wasAlive = $this->isAlive();
 		parent::setHealth($amount);
 		$this->attributeMap->getAttribute(Attribute::HEALTH)->setValue(ceil($this->getHealth()), true);
@@ -134,7 +134,7 @@ abstract class Living extends Entity implements Damageable{
 		return (int) $this->attributeMap->getAttribute(Attribute::HEALTH)->getMaxValue();
 	}
 
-	public function setMaxHealth(int $amount){
+	public function setMaxHealth(int $amount) : void{
 		$this->attributeMap->getAttribute(Attribute::HEALTH)->setMaxValue($amount);
 	}
 
@@ -142,11 +142,11 @@ abstract class Living extends Entity implements Damageable{
 		return $this->attributeMap->getAttribute(Attribute::ABSORPTION)->getValue();
 	}
 
-	public function setAbsorption(float $absorption){
+	public function setAbsorption(float $absorption) : void{
 		$this->attributeMap->getAttribute(Attribute::ABSORPTION)->setValue($absorption);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setFloat("Health", $this->getHealth(), true);
 
@@ -186,7 +186,7 @@ abstract class Living extends Entity implements Damageable{
 	/**
 	 * Removes all effects from the mob.
 	 */
-	public function removeAllEffects(){
+	public function removeAllEffects() : void{
 		foreach($this->effects as $effect){
 			$this->removeEffect($effect->getId());
 		}
@@ -197,7 +197,7 @@ abstract class Living extends Entity implements Damageable{
 	 *
 	 * @param int $effectId
 	 */
-	public function removeEffect(int $effectId){
+	public function removeEffect(int $effectId) : void{
 		if(isset($this->effects[$effectId])){
 			$effect = $this->effects[$effectId];
 			$this->server->getPluginManager()->callEvent($ev = new EntityEffectRemoveEvent($this, $effect));
@@ -221,7 +221,7 @@ abstract class Living extends Entity implements Damageable{
 	 *
 	 * @return EffectInstance|null
 	 */
-	public function getEffect(int $effectId){
+	public function getEffect(int $effectId) : ?EffectInstance{
 		return $this->effects[$effectId] ?? null;
 	}
 
@@ -292,7 +292,7 @@ abstract class Living extends Entity implements Damageable{
 	/**
 	 * Recalculates the mob's potion bubbles colour based on the active effects.
 	 */
-	protected function recalculateEffectColor(){
+	protected function recalculateEffectColor() : void{
 		/** @var Color[] $colors */
 		$colors = [];
 		$ambient = true;
@@ -323,7 +323,7 @@ abstract class Living extends Entity implements Damageable{
 	 * Sends the mob's potion effects to the specified player.
 	 * @param Player $player
 	 */
-	public function sendPotionEffects(Player $player){
+	public function sendPotionEffects(Player $player) : void{
 		foreach($this->effects as $effect){
 			$pk = new MobEffectPacket();
 			$pk->entityRuntimeId = $this->id;
@@ -374,13 +374,13 @@ abstract class Living extends Entity implements Damageable{
 	/**
 	 * Called when the entity jumps from the ground. This method adds upwards velocity to the entity.
 	 */
-	public function jump(){
+	public function jump() : void{
 		if($this->onGround){
 			$this->motionY = $this->getJumpVelocity(); //Y motion should already be 0 if we're jumping from the ground.
 		}
 	}
 
-	public function fall(float $fallDistance){
+	public function fall(float $fallDistance) : void{
 		$damage = ceil($fallDistance - 3 - ($this->hasEffect(Effect::JUMP) ? $this->getEffect(Effect::JUMP)->getEffectLevel() : 0));
 		if($damage > 0){
 			$ev = new EntityDamageEvent($this, EntityDamageEvent::CAUSE_FALL, $damage);
@@ -427,7 +427,7 @@ abstract class Living extends Entity implements Damageable{
 		return $this->armorInventory;
 	}
 
-	public function setOnFire(int $seconds){
+	public function setOnFire(int $seconds) : void{
 		parent::setOnFire($seconds - (int) min($seconds, $seconds * $this->getHighestArmorEnchantmentLevel(Enchantment::FIRE_PROTECTION) * 0.15));
 	}
 
@@ -492,7 +492,7 @@ abstract class Living extends Entity implements Damageable{
 		$this->armorInventory->setContents($armor);
 	}
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		if($this->attackTime > 0 or $this->noDamageTicks > 0){
 			$lastCause = $this->getLastDamageCause();
 			if($lastCause !== null and $lastCause->getDamage() >= $source->getDamage()){
@@ -559,7 +559,7 @@ abstract class Living extends Entity implements Damageable{
 		$this->broadcastEntityEvent(EntityEventPacket::HURT_ANIMATION);
 	}
 
-	public function knockBack(Entity $attacker, float $damage, float $x, float $z, float $base = 0.4){
+	public function knockBack(Entity $attacker, float $damage, float $x, float $z, float $base = 0.4) : void{
 		$f = sqrt($x * $x + $z * $z);
 		if($f <= 0){
 			return;
@@ -583,12 +583,12 @@ abstract class Living extends Entity implements Damageable{
 		$this->setMotion($motion);
 	}
 
-	public function kill(){
+	public function kill() : void{
 		parent::kill();
 		$this->onDeath();
 	}
 
-	protected function onDeath(){
+	protected function onDeath() : void{
 		$this->server->getPluginManager()->callEvent($ev = new EntityDeathEvent($this, $this->getDrops()));
 		foreach($ev->getDrops() as $item){
 			$this->getLevel()->dropItem($this, $item);
@@ -649,7 +649,7 @@ abstract class Living extends Entity implements Damageable{
 		return $hasUpdate;
 	}
 
-	protected function doEffectsTick(int $tickDiff = 1){
+	protected function doEffectsTick(int $tickDiff = 1) : void{
 		foreach($this->effects as $instance){
 			$type = $instance->getType();
 			if($type->canTick($instance)){
@@ -666,7 +666,7 @@ abstract class Living extends Entity implements Damageable{
 	 * Ticks the entity's air supply when it cannot breathe.
 	 * @param int $tickDiff
 	 */
-	protected function doAirSupplyTick(int $tickDiff){
+	protected function doAirSupplyTick(int $tickDiff) : void{
 		if(($respirationLevel = $this->armorInventory->getHelmet()->getEnchantmentLevel(Enchantment::RESPIRATION)) <= 0 or
 			lcg_value() <= (1 / ($respirationLevel + 1))
 		){
@@ -703,7 +703,7 @@ abstract class Living extends Entity implements Damageable{
 	 *
 	 * @param bool $value
 	 */
-	public function setBreathing(bool $value = true){
+	public function setBreathing(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_BREATHING, $value);
 	}
 
@@ -721,7 +721,7 @@ abstract class Living extends Entity implements Damageable{
 	 * Sets the number of air ticks left in the entity's air supply.
 	 * @param int $ticks
 	 */
-	public function setAirSupplyTicks(int $ticks){
+	public function setAirSupplyTicks(int $ticks) : void{
 		$this->propertyManager->setShort(self::DATA_AIR, $ticks);
 	}
 
@@ -737,7 +737,7 @@ abstract class Living extends Entity implements Damageable{
 	 * Sets the maximum amount of air ticks the air supply can hold.
 	 * @param int $ticks
 	 */
-	public function setMaxAirSupplyTicks(int $ticks){
+	public function setMaxAirSupplyTicks(int $ticks) : void{
 		$this->propertyManager->setShort(self::DATA_MAX_AIR, $ticks);
 	}
 
@@ -745,7 +745,7 @@ abstract class Living extends Entity implements Damageable{
 	 * Called when the entity's air supply ticks reaches -20 or lower. The entity will usually take damage at this point
 	 * and then the supply is reset to 0, so this method will be called roughly every second.
 	 */
-	public function onAirExpired(){
+	public function onAirExpired() : void{
 		$ev = new EntityDamageEvent($this, EntityDamageEvent::CAUSE_DROWNING, 2);
 		$this->attack($ev);
 	}
@@ -815,7 +815,7 @@ abstract class Living extends Entity implements Damageable{
 	 *
 	 * @return Block|null
 	 */
-	public function getTargetBlock(int $maxDistance, array $transparent = []){
+	public function getTargetBlock(int $maxDistance, array $transparent = []) : ?Block{
 		$line = $this->getLineOfSight($maxDistance, 1, $transparent);
 		if(!empty($line)){
 			return array_shift($line);
@@ -849,7 +849,7 @@ abstract class Living extends Entity implements Damageable{
 		$this->armorInventory->sendContents($player);
 	}
 
-	public function close(){
+	public function close() : void{
 		if(!$this->closed){
 			if($this->armorInventory !== null){
 				$this->armorInventory->removeAllViewers(true);
diff --git a/src/pocketmine/entity/Squid.php b/src/pocketmine/entity/Squid.php
index 940c2fe76..a792364d4 100644
--- a/src/pocketmine/entity/Squid.php
+++ b/src/pocketmine/entity/Squid.php
@@ -42,7 +42,7 @@ class Squid extends WaterAnimal{
 
 	private $switchDirectionTicker = 0;
 
-	public function initEntity(){
+	public function initEntity() : void{
 		$this->setMaxHealth(10);
 		parent::initEntity();
 	}
@@ -51,7 +51,7 @@ class Squid extends WaterAnimal{
 		return "Squid";
 	}
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		parent::attack($source);
 		if($source->isCancelled()){
 			return;
@@ -115,7 +115,7 @@ class Squid extends WaterAnimal{
 		return $hasUpdate;
 	}
 
-	protected function applyGravity(){
+	protected function applyGravity() : void{
 		if(!$this->isInsideOfWater()){
 			parent::applyGravity();
 		}
diff --git a/src/pocketmine/entity/Villager.php b/src/pocketmine/entity/Villager.php
index a9090e8ec..233690ca9 100644
--- a/src/pocketmine/entity/Villager.php
+++ b/src/pocketmine/entity/Villager.php
@@ -39,7 +39,7 @@ class Villager extends Creature implements NPC, Ageable{
 		return "Villager";
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		/** @var int $profession */
@@ -52,7 +52,7 @@ class Villager extends Creature implements NPC, Ageable{
 		$this->setProfession($profession);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setInt("Profession", $this->getProfession());
 	}
@@ -62,7 +62,7 @@ class Villager extends Creature implements NPC, Ageable{
 	 *
 	 * @param int $profession
 	 */
-	public function setProfession(int $profession){
+	public function setProfession(int $profession) : void{
 		$this->propertyManager->setInt(self::DATA_VARIANT, $profession);
 	}
 
diff --git a/src/pocketmine/entity/WaterAnimal.php b/src/pocketmine/entity/WaterAnimal.php
index b811f71da..1396efe6c 100644
--- a/src/pocketmine/entity/WaterAnimal.php
+++ b/src/pocketmine/entity/WaterAnimal.php
@@ -35,7 +35,7 @@ abstract class WaterAnimal extends Creature implements Ageable{
 		return $this->isInsideOfWater();
 	}
 
-	public function onAirExpired(){
+	public function onAirExpired() : void{
 		$ev = new EntityDamageEvent($this, EntityDamageEvent::CAUSE_SUFFOCATION, 2);
 		$this->attack($ev);
 	}
diff --git a/src/pocketmine/entity/object/ExperienceOrb.php b/src/pocketmine/entity/object/ExperienceOrb.php
index 6bbd1f110..4351a6ffa 100644
--- a/src/pocketmine/entity/object/ExperienceOrb.php
+++ b/src/pocketmine/entity/object/ExperienceOrb.php
@@ -100,7 +100,7 @@ class ExperienceOrb extends Entity{
 	 */
 	protected $targetPlayerRuntimeId = null;
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->age = $this->namedtag->getShort("Age", 0);
@@ -115,7 +115,7 @@ class ExperienceOrb extends Entity{
 		$this->setXpValue($value);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 
 		$this->namedtag->setShort("Age", $this->age);
@@ -210,7 +210,7 @@ class ExperienceOrb extends Entity{
 		return $hasUpdate;
 	}
 
-	protected function tryChangeMovement(){
+	protected function tryChangeMovement() : void{
 		$this->checkObstruction($this->x, $this->y, $this->z);
 		parent::tryChangeMovement();
 	}
diff --git a/src/pocketmine/entity/object/FallingBlock.php b/src/pocketmine/entity/object/FallingBlock.php
index 01400e4cd..9a1a91841 100644
--- a/src/pocketmine/entity/object/FallingBlock.php
+++ b/src/pocketmine/entity/object/FallingBlock.php
@@ -50,7 +50,7 @@ class FallingBlock extends Entity{
 
 	public $canCollide = false;
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$blockId = 0;
@@ -83,7 +83,7 @@ class FallingBlock extends Entity{
 		return false;
 	}
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		if($source->getCause() === EntityDamageEvent::CAUSE_VOID){
 			parent::attack($source);
 		}
@@ -126,15 +126,15 @@ class FallingBlock extends Entity{
 		return $hasUpdate;
 	}
 
-	public function getBlock(){
+	public function getBlock() : int{
 		return $this->block->getId();
 	}
 
-	public function getDamage(){
+	public function getDamage() : int{
 		return $this->block->getDamage();
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		$this->namedtag->setInt("TileID", $this->block->getId(), true);
 		$this->namedtag->setByte("Data", $this->block->getDamage());
 	}
diff --git a/src/pocketmine/entity/object/ItemEntity.php b/src/pocketmine/entity/object/ItemEntity.php
index 7f6a5d5bb..00179186d 100644
--- a/src/pocketmine/entity/object/ItemEntity.php
+++ b/src/pocketmine/entity/object/ItemEntity.php
@@ -53,7 +53,7 @@ class ItemEntity extends Entity{
 
 	public $canCollide = false;
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->setMaxHealth(5);
@@ -106,7 +106,7 @@ class ItemEntity extends Entity{
 		return $hasUpdate;
 	}
 
-	protected function tryChangeMovement(){
+	protected function tryChangeMovement() : void{
 		$this->checkObstruction($this->x, $this->y, $this->z);
 		parent::tryChangeMovement();
 	}
@@ -115,7 +115,7 @@ class ItemEntity extends Entity{
 		return true;
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setTag($this->item->nbtSerialize(-1, "Item"));
 		$this->namedtag->setShort("Health", (int) $this->getHealth());
@@ -154,7 +154,7 @@ class ItemEntity extends Entity{
 	/**
 	 * @param int $delay
 	 */
-	public function setPickupDelay(int $delay){
+	public function setPickupDelay(int $delay) : void{
 		$this->pickupDelay = $delay;
 	}
 
@@ -168,7 +168,7 @@ class ItemEntity extends Entity{
 	/**
 	 * @param string $owner
 	 */
-	public function setOwner(string $owner){
+	public function setOwner(string $owner) : void{
 		$this->owner = $owner;
 	}
 
@@ -182,7 +182,7 @@ class ItemEntity extends Entity{
 	/**
 	 * @param string $thrower
 	 */
-	public function setThrower(string $thrower){
+	public function setThrower(string $thrower) : void{
 		$this->thrower = $thrower;
 	}
 
@@ -197,7 +197,7 @@ class ItemEntity extends Entity{
 		$player->dataPacket($pk);
 	}
 
-	public function onCollideWithPlayer(Player $player){
+	public function onCollideWithPlayer(Player $player) : void{
 		if($this->getPickupDelay() > 0){
 			return;
 		}
diff --git a/src/pocketmine/entity/object/Painting.php b/src/pocketmine/entity/object/Painting.php
index 54e44a7d1..6279f0dd7 100644
--- a/src/pocketmine/entity/object/Painting.php
+++ b/src/pocketmine/entity/object/Painting.php
@@ -70,13 +70,13 @@ class Painting extends Entity{
 		parent::__construct($level, $nbt);
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		$this->setMaxHealth(1);
 		$this->setHealth(1);
 		parent::initEntity();
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setInt("TileX", (int) $this->blockIn->x);
 		$this->namedtag->setInt("TileY", (int) $this->blockIn->y);
@@ -86,7 +86,7 @@ class Painting extends Entity{
 		$this->namedtag->setByte("Direction", (int) $this->direction); //Save both for full compatibility
 	}
 
-	public function kill(){
+	public function kill() : void{
 		parent::kill();
 
 		$drops = true;
@@ -138,7 +138,7 @@ class Painting extends Entity{
 		return false;
 	}
 
-	protected function updateMovement(bool $teleport = false){
+	protected function updateMovement(bool $teleport = false) : void{
 
 	}
 
@@ -166,7 +166,7 @@ class Painting extends Entity{
 		return PaintingMotive::getMotiveByName($this->motive);
 	}
 
-	public function getDirection() : int{
+	public function getDirection() : ?int{
 		return $this->direction;
 	}
 
diff --git a/src/pocketmine/entity/object/PrimedTNT.php b/src/pocketmine/entity/object/PrimedTNT.php
index e1a12b7db..b7839c2b3 100644
--- a/src/pocketmine/entity/object/PrimedTNT.php
+++ b/src/pocketmine/entity/object/PrimedTNT.php
@@ -47,13 +47,13 @@ class PrimedTNT extends Entity implements Explosive{
 	public $canCollide = false;
 
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		if($source->getCause() === EntityDamageEvent::CAUSE_VOID){
 			parent::attack($source);
 		}
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		if($this->namedtag->hasTag("Fuse", ShortTag::class)){
@@ -73,7 +73,7 @@ class PrimedTNT extends Entity implements Explosive{
 		return false;
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setShort("Fuse", $this->fuse, true); //older versions incorrectly saved this as a byte
 	}
@@ -101,7 +101,7 @@ class PrimedTNT extends Entity implements Explosive{
 		return $hasUpdate or $this->fuse >= 0;
 	}
 
-	public function explode(){
+	public function explode() : void{
 		$this->server->getPluginManager()->callEvent($ev = new ExplosionPrimeEvent($this, 4));
 
 		if(!$ev->isCancelled()){
diff --git a/src/pocketmine/entity/projectile/Arrow.php b/src/pocketmine/entity/projectile/Arrow.php
index e63d44695..9bfab053b 100644
--- a/src/pocketmine/entity/projectile/Arrow.php
+++ b/src/pocketmine/entity/projectile/Arrow.php
@@ -48,7 +48,7 @@ class Arrow extends Projectile{
 
 	protected $damage = 2;
 
-	public function __construct(Level $level, CompoundTag $nbt, Entity $shootingEntity = null, bool $critical = false){
+	public function __construct(Level $level, CompoundTag $nbt, ?Entity $shootingEntity = null, bool $critical = false){
 		parent::__construct($level, $nbt, $shootingEntity);
 		$this->setCritical($critical);
 	}
@@ -57,7 +57,7 @@ class Arrow extends Projectile{
 		return $this->getGenericFlag(self::DATA_FLAG_CRITICAL);
 	}
 
-	public function setCritical(bool $value = true){
+	public function setCritical(bool $value = true) : void{
 		$this->setGenericFlag(self::DATA_FLAG_CRITICAL, $value);
 	}
 
@@ -95,7 +95,7 @@ class Arrow extends Projectile{
 		$this->broadcastEntityEvent(EntityEventPacket::ARROW_SHAKE, 7); //7 ticks
 	}
 
-	public function onCollideWithPlayer(Player $player){
+	public function onCollideWithPlayer(Player $player) : void{
 		if($this->blockHit === null){
 			return;
 		}
diff --git a/src/pocketmine/entity/projectile/Projectile.php b/src/pocketmine/entity/projectile/Projectile.php
index f70ecf939..b9c96cb7d 100644
--- a/src/pocketmine/entity/projectile/Projectile.php
+++ b/src/pocketmine/entity/projectile/Projectile.php
@@ -55,20 +55,20 @@ abstract class Projectile extends Entity{
 	/** @var int|null */
 	protected $blockHitData;
 
-	public function __construct(Level $level, CompoundTag $nbt, Entity $shootingEntity = null){
+	public function __construct(Level $level, CompoundTag $nbt, ?Entity $shootingEntity = null){
 		parent::__construct($level, $nbt);
 		if($shootingEntity !== null){
 			$this->setOwningEntity($shootingEntity);
 		}
 	}
 
-	public function attack(EntityDamageEvent $source){
+	public function attack(EntityDamageEvent $source) : void{
 		if($source->getCause() === EntityDamageEvent::CAUSE_VOID){
 			parent::attack($source);
 		}
 	}
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->setMaxHealth(1);
@@ -120,7 +120,7 @@ abstract class Projectile extends Entity{
 		return (int) ceil(sqrt($this->motionX ** 2 + $this->motionY ** 2 + $this->motionZ ** 2) * $this->damage);
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 
 		$this->namedtag->setShort("Age", $this->age);
diff --git a/src/pocketmine/entity/projectile/SplashPotion.php b/src/pocketmine/entity/projectile/SplashPotion.php
index e65bd6361..434f854ca 100644
--- a/src/pocketmine/entity/projectile/SplashPotion.php
+++ b/src/pocketmine/entity/projectile/SplashPotion.php
@@ -42,13 +42,13 @@ class SplashPotion extends Throwable{
 	protected $gravity = 0.05;
 	protected $drag = 0.01;
 
-	protected function initEntity(){
+	protected function initEntity() : void{
 		parent::initEntity();
 
 		$this->setPotionId($this->namedtag->getShort("PotionId", 0));
 	}
 
-	public function saveNBT(){
+	public function saveNBT() : void{
 		parent::saveNBT();
 		$this->namedtag->setShort("PotionId", $this->getPotionId());
 	}