diff --git a/src/pocketmine/PocketMine.php b/src/pocketmine/PocketMine.php
index ce43925823..6ba4cad8ec 100644
--- a/src/pocketmine/PocketMine.php
+++ b/src/pocketmine/PocketMine.php
@@ -194,6 +194,14 @@ namespace pocketmine {
 		mkdir(\pocketmine\DATA, 0777, true);
 	}
 
+	define('pocketmine\LOCK_FILE_PATH', \pocketmine\DATA . 'server.lock');
+	define('pocketmine\LOCK_FILE', fopen(\pocketmine\LOCK_FILE_PATH, "cb"));
+	if(!flock(\pocketmine\LOCK_FILE, LOCK_EX | LOCK_NB)){
+		critical_error("Another " . \pocketmine\NAME . " instance is already using this folder (" . realpath(\pocketmine\DATA) . ").");
+		critical_error("Please stop the other server first before running a new one.");
+		exit(1);
+	}
+
 	//Logger has a dependency on timezone
 	Timezone::init();
 
diff --git a/src/pocketmine/command/defaults/KillCommand.php b/src/pocketmine/command/defaults/KillCommand.php
index 7d2216915e..b6326aedd7 100644
--- a/src/pocketmine/command/defaults/KillCommand.php
+++ b/src/pocketmine/command/defaults/KillCommand.php
@@ -55,7 +55,7 @@ class KillCommand extends VanillaCommand{
 
 		if(count($args) === 1){
 			if(!$sender->hasPermission("pocketmine.command.kill.other")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
@@ -74,7 +74,7 @@ class KillCommand extends VanillaCommand{
 
 		if($sender instanceof Player){
 			if(!$sender->hasPermission("pocketmine.command.kill.self")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
diff --git a/src/pocketmine/command/defaults/TimeCommand.php b/src/pocketmine/command/defaults/TimeCommand.php
index 2289e3f716..0ca094c9cc 100644
--- a/src/pocketmine/command/defaults/TimeCommand.php
+++ b/src/pocketmine/command/defaults/TimeCommand.php
@@ -50,7 +50,7 @@ class TimeCommand extends VanillaCommand{
 
 		if($args[0] === "start"){
 			if(!$sender->hasPermission("pocketmine.command.time.start")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
@@ -61,7 +61,7 @@ class TimeCommand extends VanillaCommand{
 			return true;
 		}elseif($args[0] === "stop"){
 			if(!$sender->hasPermission("pocketmine.command.time.stop")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
@@ -72,7 +72,7 @@ class TimeCommand extends VanillaCommand{
 			return true;
 		}elseif($args[0] === "query"){
 			if(!$sender->hasPermission("pocketmine.command.time.query")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
@@ -92,7 +92,7 @@ class TimeCommand extends VanillaCommand{
 
 		if($args[0] === "set"){
 			if(!$sender->hasPermission("pocketmine.command.time.set")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
@@ -111,7 +111,7 @@ class TimeCommand extends VanillaCommand{
 			Command::broadcastCommandMessage($sender, new TranslationContainer("commands.time.set", [$value]));
 		}elseif($args[0] === "add"){
 			if(!$sender->hasPermission("pocketmine.command.time.add")){
-				$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+				$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 				return true;
 			}
diff --git a/src/pocketmine/command/defaults/WhitelistCommand.php b/src/pocketmine/command/defaults/WhitelistCommand.php
index 527bf91b09..c5d988f583 100644
--- a/src/pocketmine/command/defaults/WhitelistCommand.php
+++ b/src/pocketmine/command/defaults/WhitelistCommand.php
@@ -117,7 +117,7 @@ class WhitelistCommand extends VanillaCommand{
 
 	private function badPerm(CommandSender $sender, string $perm) : bool{
 		if(!$sender->hasPermission("pocketmine.command.whitelist.$perm")){
-			$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));
+			$sender->sendMessage($sender->getServer()->getLanguage()->translateString(TextFormat::RED . "%commands.generic.permission"));
 
 			return true;
 		}
diff --git a/src/pocketmine/entity/Entity.php b/src/pocketmine/entity/Entity.php
index b45215a349..126d2923d4 100644
--- a/src/pocketmine/entity/Entity.php
+++ b/src/pocketmine/entity/Entity.php
@@ -94,6 +94,10 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_TYPE_LONG = 7;
 	public const DATA_TYPE_VECTOR3F = 8;
 
+	/*
+	 * Readers beware: this isn't a nice list. Some of the properties have different types for different entities, and
+	 * are used for entirely different things.
+	 */
 	public const DATA_FLAGS = 0;
 	public const DATA_HEALTH = 1; //int (minecart/boat)
 	public const DATA_VARIANT = 2; //int
@@ -111,17 +115,21 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_PADDLE_TIME_RIGHT = 14; //float
 	public const DATA_EXPERIENCE_VALUE = 15; //int (xp orb)
 	public const DATA_MINECART_DISPLAY_BLOCK = 16; //int (id | (data << 16))
+	public const DATA_HORSE_FLAGS = 16; //int
+	/* 16 (byte) used by wither skull */
 	public const DATA_MINECART_DISPLAY_OFFSET = 17; //int
+	public const DATA_SHOOTER_ID = 17; //long (used by arrows)
 	public const DATA_MINECART_HAS_DISPLAY = 18; //byte (must be 1 for minecart to show block inside)
-
-	//TODO: add more properties
-
+	public const DATA_HORSE_TYPE = 19; //byte
+	/* 20 (unknown)
+	 * 21 (unknown) */
+	public const DATA_CHARGE_AMOUNT = 22; //int8, used for ghasts and also crossbow charging
 	public const DATA_ENDERMAN_HELD_ITEM_ID = 23; //short
 	public const DATA_ENTITY_AGE = 24; //short
-
-	/* 26 (byte) player-specific flags
-	 * 27 (int) player "index"?
-	 * 28 (block coords) bed position */
+	/* 25 (int) used by horse, (byte) used by witch */
+	public const DATA_PLAYER_FLAGS = 26; //byte
+	public const DATA_PLAYER_INDEX = 27; //int, used for marker colours and agent nametag colours
+	public const DATA_PLAYER_BED_POSITION = 28; //blockpos
 	public const DATA_FIREBALL_POWER_X = 29; //float
 	public const DATA_FIREBALL_POWER_Y = 30;
 	public const DATA_FIREBALL_POWER_Z = 31;
@@ -132,7 +140,7 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_POTION_AUX_VALUE = 36; //short
 	public const DATA_LEAD_HOLDER_EID = 37; //long
 	public const DATA_SCALE = 38; //float
-	public const DATA_INTERACTIVE_TAG = 39; //string (button text)
+	public const DATA_HAS_NPC_COMPONENT = 39; //byte (???)
 	public const DATA_NPC_SKIN_ID = 40; //string
 	public const DATA_URL_TAG = 41; //string
 	public const DATA_MAX_AIR = 42; //short
@@ -182,8 +190,8 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_BOAT_BUBBLE_TIME = 86; //int (time in bubble column)
 	public const DATA_PLAYER_AGENT_EID = 87; //long
 	/* 88 (float) related to panda sitting
-	 * 89 (float) related to panda sitting
-	 * 90 (unknown) */
+	 * 89 (float) related to panda sitting */
+	public const DATA_EAT_COUNTER = 90; //int (used by pandas)
 	public const DATA_FLAGS2 = 91; //long (extended data flags)
 	/* 92 (float) related to panda lying down
 	 * 93 (float) related to panda lying down */
@@ -192,7 +200,9 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_AREA_EFFECT_CLOUD_RADIUS_PER_TICK = 96; //float, usually negative
 	public const DATA_AREA_EFFECT_CLOUD_RADIUS_CHANGE_ON_PICKUP = 97; //float
 	public const DATA_AREA_EFFECT_CLOUD_PICKUP_COUNT = 98; //int
-
+	public const DATA_INTERACTIVE_TAG = 99; //string (button text)
+	public const DATA_TRADE_TIER = 100; //int
+	public const DATA_MAX_TRADE_TIER = 101; //int
 
 	public const DATA_FLAG_ONFIRE = 0;
 	public const DATA_FLAG_SNEAKING = 1;
@@ -265,6 +275,18 @@ abstract class Entity extends Location implements Metadatable, EntityIds{
 	public const DATA_FLAG_IN_SCAFFOLDING = 68;
 	public const DATA_FLAG_OVER_SCAFFOLDING = 69;
 	public const DATA_FLAG_FALL_THROUGH_SCAFFOLDING = 70;
+	public const DATA_FLAG_BLOCKING = 71; //shield
+	public const DATA_FLAG_DISABLE_BLOCKING = 72;
+	//73 is set when a player is attacked while using shield, unclear on purpose
+	public const DATA_FLAG_SLEEPING = 74;
+	//75 related to sleeping, unclear usage
+	public const DATA_FLAG_TRADE_INTEREST = 76;
+	public const DATA_FLAG_DOOR_BREAKER = 77; //...
+	public const DATA_FLAG_BREAKING_OBSTRUCTION = 78;
+	public const DATA_FLAG_DOOR_OPENER = 79; //...
+
+	public const DATA_PLAYER_FLAG_SLEEP = 1;
+	public const DATA_PLAYER_FLAG_DEAD = 2; //TODO: CHECK
 
 
 	/**
diff --git a/src/pocketmine/entity/Human.php b/src/pocketmine/entity/Human.php
index c116fb2ba4..5beeb8b66e 100644
--- a/src/pocketmine/entity/Human.php
+++ b/src/pocketmine/entity/Human.php
@@ -73,13 +73,6 @@ use const INT32_MIN;
 
 class Human extends Creature implements ProjectileSource, InventoryHolder{
 
-	public const DATA_PLAYER_FLAG_SLEEP = 1;
-	public const DATA_PLAYER_FLAG_DEAD = 2; //TODO: CHECK
-
-	public const DATA_PLAYER_FLAGS = 26;
-
-	public const DATA_PLAYER_BED_POSITION = 28;
-
 	/** @var PlayerInventory */
 	protected $inventory;
 
diff --git a/src/pocketmine/entity/projectile/Projectile.php b/src/pocketmine/entity/projectile/Projectile.php
index 57bb71307a..ee29edf4e8 100644
--- a/src/pocketmine/entity/projectile/Projectile.php
+++ b/src/pocketmine/entity/projectile/Projectile.php
@@ -52,8 +52,6 @@ use const PHP_INT_MAX;
 
 abstract class Projectile extends Entity{
 
-	public const DATA_SHOOTER_ID = 17;
-
 	/** @var float */
 	protected $damage = 0.0;
 
diff --git a/src/pocketmine/utils/TextFormat.php b/src/pocketmine/utils/TextFormat.php
index 6e5f817e95..90d1441d83 100644
--- a/src/pocketmine/utils/TextFormat.php
+++ b/src/pocketmine/utils/TextFormat.php
@@ -74,7 +74,7 @@ abstract class TextFormat{
 	 * @return array
 	 */
 	public static function tokenize(string $string) : array{
-		return preg_split("/(" . TextFormat::ESCAPE . "[0-9a-fk-or])/", $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
+		return preg_split("/(" . TextFormat::ESCAPE . "[0-9a-fk-or])/u", $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
 	}
 
 	/**