diff --git a/src/pocketmine/Player.php b/src/pocketmine/Player.php
index 58de569b4..a36568a87 100644
--- a/src/pocketmine/Player.php
+++ b/src/pocketmine/Player.php
@@ -1560,7 +1560,7 @@ class Player extends Human implements CommandSender, InventoryHolder, ChunkLoade
 		$delta = pow($this->lastX - $to->x, 2) + pow($this->lastY - $to->y, 2) + pow($this->lastZ - $to->z, 2);
 		$deltaAngle = abs($this->lastYaw - $to->yaw) + abs($this->lastPitch - $to->pitch);
 
-		if(!$revert and ($delta > (1 / 16) or $deltaAngle > 10)){
+		if(!$revert and ($delta > 0.0001 or $deltaAngle > 1.0)){
 
 			$isFirst = ($this->lastX === null or $this->lastY === null or $this->lastZ === null);
 
@@ -1583,7 +1583,6 @@ class Player extends Human implements CommandSender, InventoryHolder, ChunkLoade
 						$this->level->addEntityMovement($this->x >> 4, $this->z >> 4, $this->getId(), $this->x, $this->y + $this->getEyeHeight(), $this->z, $this->yaw, $this->pitch, $this->yaw);
 
 						$distance = $from->distance($to);
-
 						//TODO: check swimming (adds 0.015 exhaustion in MCPE)
 						if($this->isSprinting()){
 							$this->exhaust(0.1 * $distance, PlayerExhaustEvent::CAUSE_SPRINTING);
@@ -3274,7 +3273,14 @@ class Player extends Human implements CommandSender, InventoryHolder, ChunkLoade
 
 		$tile = $this->level->getTile($this->temporalVector->setComponents($packet->x, $packet->y, $packet->z));
 		if($tile instanceof ItemFrame){
+			$ev = new PlayerInteractEvent($this, $this->inventory->getItemInHand(), $tile->getBlock(), 5 - $tile->getBlock()->getDamage(), PlayerInteractEvent::LEFT_CLICK_BLOCK);
+			$this->server->getPluginManager()->callEvent($ev);
+
 			if($this->isSpectator()){
+				$ev->setCancelled();
+			}
+
+			if($ev->isCancelled()){
 				$tile->spawnTo($this);
 				return true;
 			}
diff --git a/src/pocketmine/entity/Effect.php b/src/pocketmine/entity/Effect.php
index a5327dbde..942ec62f5 100644
--- a/src/pocketmine/entity/Effect.php
+++ b/src/pocketmine/entity/Effect.php
@@ -222,9 +222,17 @@ class Effect{
 		return $this;
 	}
 
+	/**
+	 * Returns the level of this effect, which is always one higher than the amplifier.
+	 *
+	 * @return int
+	 */
+	public function getEffectLevel() : int{
+		return $this->amplifier + 1;
+	}
+
 	/**
 	 * Returns the amplifier of this effect.
-	 * TODO: fix mess of amplifier used instead of level for effect calculation.
 	 *
 	 * @return int
 	 */
@@ -337,19 +345,19 @@ class Effect{
 
 			case Effect::HUNGER:
 				if($entity instanceof Human){
-					$entity->exhaust(0.5 * $this->amplifier, PlayerExhaustEvent::CAUSE_POTION);
+					$entity->exhaust(0.5 * $this->getEffectLevel(), PlayerExhaustEvent::CAUSE_POTION);
 				}
 				break;
 			case Effect::INSTANT_HEALTH:
 				//TODO: add particles (witch spell)
 				if($entity->getHealth() < $entity->getMaxHealth()){
-					$amount = 2 * (2 ** (($this->amplifier + 1) % 32));
+					$amount = 2 * (2 ** ($this->getEffectLevel() % 32));
 					$entity->heal($amount, new EntityRegainHealthEvent($entity, $amount, EntityRegainHealthEvent::CAUSE_MAGIC));
 				}
 				break;
 			case Effect::INSTANT_DAMAGE:
 				//TODO: add particles (witch spell)
-				$amount = 2 * (2 ** (($this->amplifier + 1) % 32));
+				$amount = 2 * (2 ** ($this->getEffectLevel() % 32));
 				$entity->attack($amount, new EntityDamageEvent($entity, EntityDamageEvent::CAUSE_MAGIC, $amount));
 				break;
 		}
@@ -410,42 +418,41 @@ class Effect{
 			case Effect::SPEED:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::MOVEMENT_SPEED);
 				if($ev->willModify() and $oldEffect !== null){
-					$speed = $attr->getValue() / (1 + 0.2 * $oldEffect->getAmplifier());
+					$speed = $attr->getValue() / (1 + 0.2 * $oldEffect->getEffectLevel());
 				}else{
 					$speed = $attr->getValue();
 				}
-				$speed *= (1 + 0.2 * $this->amplifier);
+				$speed *= (1 + 0.2 * $this->getEffectLevel());
 				$attr->setValue($speed);
 				break;
 			case Effect::SLOWNESS:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::MOVEMENT_SPEED);
 				if($ev->willModify() and $oldEffect !== null){
-					$speed = $attr->getValue() / (1 - 0.15 * $oldEffect->getAmplifier());
+					$speed = $attr->getValue() / (1 - 0.15 * $oldEffect->getEffectLevel());
 				}else{
 					$speed = $attr->getValue();
 				}
-				$speed *= (1 - 0.15 * $this->amplifier);
+				$speed *= (1 - 0.15 * $this->getEffectLevel());
 				$attr->setValue($speed, true);
 				break;
 
 			case Effect::HEALTH_BOOST:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::HEALTH);
 				if($ev->willModify() and $oldEffect !== null){
-					$max = $attr->getMaxValue() - (4 * ($oldEffect->getAmplifier() + 1));
+					$max = $attr->getMaxValue() - (4 * $oldEffect->getEffectLevel());
 				}else{
 					$max = $attr->getMaxValue();
 				}
 
-				$max += (4 * ($this->amplifier + 1));
+				$max += (4 * $this->getEffectLevel());
 				$attr->setMaxValue($max);
 				break;
 			case Effect::ABSORPTION:
-				$new = (4 * ($this->amplifier + 1));
+				$new = (4 * $this->getEffectLevel());
 				if($new > $entity->getAbsorption()){
 					$entity->setAbsorption($new);
 				}
 				break;
-
 		}
 	}
 
@@ -475,15 +482,15 @@ class Effect{
 				break;
 			case Effect::SPEED:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::MOVEMENT_SPEED);
-				$attr->setValue($attr->getValue() / (1 + 0.2 * $this->amplifier));
+				$attr->setValue($attr->getValue() / (1 + 0.2 * $this->getEffectLevel()));
 				break;
 			case Effect::SLOWNESS:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::MOVEMENT_SPEED);
-				$attr->setValue($attr->getValue() / (1 - 0.15 * $this->amplifier));
+				$attr->setValue($attr->getValue() / (1 - 0.15 * $this->getEffectLevel()));
 				break;
 			case Effect::HEALTH_BOOST:
 				$attr = $entity->getAttributeMap()->getAttribute(Attribute::HEALTH);
-				$attr->setMaxValue($attr->getMaxValue() - (4 * ($this->amplifier + 1)));
+				$attr->setMaxValue($attr->getMaxValue() - 4 * $this->getEffectLevel());
 				break;
 			case Effect::ABSORPTION:
 				$entity->setAbsorption(0);
diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index 8af4c849b..0e96ea789 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/src/pocketmine/entity/Entity.php
@@ -455,6 +455,7 @@ abstract class Entity extends Location implements Metadatable{
 
 		$this->width *= $multiplier;
 		$this->height *= $multiplier;
+		$this->eyeHeight *= $multiplier;
 		$halfWidth = $this->width / 2;
 
 		$this->boundingBox->setBounds(
@@ -467,8 +468,6 @@ abstract class Entity extends Location implements Metadatable{
 		);
 
 		$this->setDataProperty(self::DATA_SCALE, self::DATA_TYPE_FLOAT, $value);
-		$this->setDataProperty(self::DATA_BOUNDING_BOX_WIDTH, self::DATA_TYPE_FLOAT, $this->width);
-		$this->setDataProperty(self::DATA_BOUNDING_BOX_HEIGHT, self::DATA_TYPE_FLOAT, $this->height);
 	}
 
 	public function isSneaking(){
@@ -666,10 +665,10 @@ abstract class Entity extends Location implements Metadatable{
 		foreach($this->effects as $effect){
 			if($effect->isVisible() and $effect->hasBubbles()){
 				$c = $effect->getColor();
-				$color[0] += $c[0] * ($effect->getAmplifier() + 1);
-				$color[1] += $c[1] * ($effect->getAmplifier() + 1);
-				$color[2] += $c[2] * ($effect->getAmplifier() + 1);
-				$count += $effect->getAmplifier() + 1;
+				$color[0] += $c[0] * $effect->getEffectLevel();
+				$color[1] += $c[1] * $effect->getEffectLevel();
+				$color[2] += $c[2] * $effect->getEffectLevel();
+				$count += $effect->getEffectLevel();
 				if(!$effect->isAmbient()){
 					$ambient = false;
 				}
@@ -1332,7 +1331,7 @@ abstract class Entity extends Location implements Metadatable{
 	}
 
 	public function fall($fallDistance){
-		$damage = floor($fallDistance - 3 - ($this->hasEffect(Effect::JUMP) ? $this->getEffect(Effect::JUMP)->getAmplifier() + 1 : 0));
+		$damage = floor($fallDistance - 3 - ($this->hasEffect(Effect::JUMP) ? $this->getEffect(Effect::JUMP)->getEffectLevel() : 0));
 		if($damage > 0){
 			$ev = new EntityDamageEvent($this, EntityDamageEvent::CAUSE_FALL, $damage);
 			$this->attack($ev->getFinalDamage(), $ev);
@@ -1455,6 +1454,8 @@ abstract class Entity extends Location implements Metadatable{
 			return true;
 		}
 
+		$this->blocksAround = null;
+
 		if($this->keepMovement){
 			$this->boundingBox->offset($dx, $dy, $dz);
 			$this->setPosition($this->temporalVector->setComponents(($this->boundingBox->minX + $this->boundingBox->maxX) / 2, $this->boundingBox->minY, ($this->boundingBox->minZ + $this->boundingBox->maxZ) / 2));
@@ -1583,7 +1584,7 @@ abstract class Entity extends Location implements Metadatable{
 			$this->z = ($this->boundingBox->minZ + $this->boundingBox->maxZ) / 2;
 
 			$this->checkChunks();
-
+			$this->checkBlockCollision();
 			$this->checkGroundState($movX, $movY, $movZ, $dx, $dy, $dz);
 			$this->updateFallState($dy, $this->onGround);
 
diff --git a/src/pocketmine/entity/Living.php b/src/pocketmine/entity/Living.php
index e45131d38..8e58880d6 100644
--- a/src/pocketmine/entity/Living.php
+++ b/src/pocketmine/entity/Living.php
@@ -122,7 +122,7 @@ abstract class Living extends Entity implements Damageable{
 	 * @return float
 	 */
 	public function getJumpVelocity() : float{
-		return $this->jumpVelocity + ($this->hasEffect(Effect::JUMP) ? (($this->getEffect(Effect::JUMP)->getAmplifier() + 1) / 10) : 0);
+		return $this->jumpVelocity + ($this->hasEffect(Effect::JUMP) ? ($this->getEffect(Effect::JUMP)->getEffectLevel() / 10) : 0);
 	}
 
 	/**
diff --git a/src/pocketmine/event/entity/EntityDamageByEntityEvent.php b/src/pocketmine/event/entity/EntityDamageByEntityEvent.php
index ea6228ae1..833445730 100644
--- a/src/pocketmine/event/entity/EntityDamageByEntityEvent.php
+++ b/src/pocketmine/event/entity/EntityDamageByEntityEvent.php
@@ -50,11 +50,11 @@ class EntityDamageByEntityEvent extends EntityDamageEvent{
 
 	protected function addAttackerModifiers(Entity $damager){
 		if($damager->hasEffect(Effect::STRENGTH)){
-			$this->setDamage($this->getDamage(self::MODIFIER_BASE) * 0.3 * ($damager->getEffect(Effect::STRENGTH)->getAmplifier() + 1), self::MODIFIER_STRENGTH);
+			$this->setDamage($this->getDamage(self::MODIFIER_BASE) * 0.3 * $damager->getEffect(Effect::STRENGTH)->getEffectLevel(), self::MODIFIER_STRENGTH);
 		}
 
 		if($damager->hasEffect(Effect::WEAKNESS)){
-			$this->setDamage(-($this->getDamage(self::MODIFIER_BASE) * 0.2 * ($damager->getEffect(Effect::WEAKNESS)->getAmplifier() + 1)), self::MODIFIER_WEAKNESS);
+			$this->setDamage(-($this->getDamage(self::MODIFIER_BASE) * 0.2 * $damager->getEffect(Effect::WEAKNESS)->getEffectLevel()), self::MODIFIER_WEAKNESS);
 		}
 	}
 
diff --git a/src/pocketmine/event/entity/EntityDamageEvent.php b/src/pocketmine/event/entity/EntityDamageEvent.php
index 57b77a629..d3eac739e 100644
--- a/src/pocketmine/event/entity/EntityDamageEvent.php
+++ b/src/pocketmine/event/entity/EntityDamageEvent.php
@@ -86,7 +86,7 @@ class EntityDamageEvent extends EntityEvent implements Cancellable{
 		}
 
 		if($entity->hasEffect(Effect::DAMAGE_RESISTANCE)){
-			$this->setDamage(-($this->getDamage(self::MODIFIER_BASE) * 0.20 * ($entity->getEffect(Effect::DAMAGE_RESISTANCE)->getAmplifier() + 1)), self::MODIFIER_RESISTANCE);
+			$this->setDamage(-($this->getDamage(self::MODIFIER_BASE) * 0.20 * $entity->getEffect(Effect::DAMAGE_RESISTANCE)->getEffectLevel()), self::MODIFIER_RESISTANCE);
 		}
 	}
 
diff --git a/src/pocketmine/level/Level.php b/src/pocketmine/level/Level.php
index 827a1e9a3..1f9aea008 100644
--- a/src/pocketmine/level/Level.php
+++ b/src/pocketmine/level/Level.php
@@ -1612,11 +1612,11 @@ class Level implements ChunkManager, Metadatable{
 			}
 
 			if($player->hasEffect(Effect::HASTE)){
-				$breakTime *= 1 - (0.2 * ($player->getEffect(Effect::HASTE)->getAmplifier() + 1));
+				$breakTime *= 1 - (0.2 * $player->getEffect(Effect::HASTE)->getEffectLevel());
 			}
 
 			if($player->hasEffect(Effect::MINING_FATIGUE)){
-				$breakTime *= 1 + (0.3 * ($player->getEffect(Effect::MINING_FATIGUE)->getAmplifier() + 1));
+				$breakTime *= 1 + (0.3 * $player->getEffect(Effect::MINING_FATIGUE)->getEffectLevel());
 			}
 
 			$breakTime -= 1; //1 tick compensation