diff --git a/src/pocketmine/Player.php b/src/pocketmine/Player.php
index 330f06ca6..f1985bc04 100644
--- a/src/pocketmine/Player.php
+++ b/src/pocketmine/Player.php
@@ -571,14 +571,14 @@ class Player extends Human implements CommandSender, InventoryHolder, ChunkLoade
 	public function setDisplayName($name){
 		$this->displayName = $name;
 		if($this->spawned){
-			$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getDisplayName(), $this->isSkinSlim(), $this->getSkinData());
+			$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getDisplayName(), $this->getSkinName(), $this->getSkinData());
 		}
 	}
 
-	public function setSkin($str, $isSlim = false){
-		parent::setSkin($str, $isSlim);
+	public function setSkin($str, $skinName){
+		parent::setSkin($str, $skinName);
 		if($this->spawned){
-			$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getDisplayName(), $isSlim, $str);
+			$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getDisplayName(), $skinName, $str);
 		}
 	}
 
@@ -1856,7 +1856,7 @@ class Player extends Human implements CommandSender, InventoryHolder, ChunkLoade
 					break;
 				}
 
-				$this->setSkin($packet->skin, $packet->slim);
+				$this->setSkin($packet->skin, $packet->skinName);
 
 				$this->server->getPluginManager()->callEvent($ev = new PlayerPreLoginEvent($this, "Plugin reason"));
 				if($ev->isCancelled()){
diff --git a/src/pocketmine/PocketMine.php b/src/pocketmine/PocketMine.php
index b284c885f..a4facf3dc 100644
--- a/src/pocketmine/PocketMine.php
+++ b/src/pocketmine/PocketMine.php
@@ -73,10 +73,10 @@ namespace pocketmine {
 	use pocketmine\wizard\Installer;
 
 	const VERSION = "1.6dev";
-	const API_VERSION = "1.13.0";
+	const API_VERSION = "1.13.1";
 	const CODENAME = "[REDACTED]";
-	const MINECRAFT_VERSION = "v0.13.0 alpha";
-	const MINECRAFT_VERSION_NETWORK = "0.13.0";
+	const MINECRAFT_VERSION = "v0.13.1 alpha";
+	const MINECRAFT_VERSION_NETWORK = "0.13.1";
 
 	/*
 	 * Startup code. Do not look at it, it may harm you.
diff --git a/src/pocketmine/Server.php b/src/pocketmine/Server.php
index a41e1b039..93452e7c4 100644
--- a/src/pocketmine/Server.php
+++ b/src/pocketmine/Server.php
@@ -2248,7 +2248,7 @@ class Server{
 	public function addOnlinePlayer(Player $player){
 		$this->playerList[$player->getRawUniqueId()] = $player;
 
-		$this->updatePlayerListData($player->getUniqueId(), $player->getId(), $player->getDisplayName(), $player->isSkinSlim(), $player->getSkinData());
+		$this->updatePlayerListData($player->getUniqueId(), $player->getId(), $player->getDisplayName(), $player->getSkinName(), $player->getSkinData());
 	}
 
 	public function removeOnlinePlayer(Player $player){
@@ -2262,10 +2262,10 @@ class Server{
 		}
 	}
 
-	public function updatePlayerListData(UUID $uuid, $entityId, $name, $isSlim, $skinData, array $players = null){
+	public function updatePlayerListData(UUID $uuid, $entityId, $name, $skinName, $skinData, array $players = null){
 		$pk = new PlayerListPacket();
 		$pk->type = PlayerListPacket::TYPE_ADD;
-		$pk->entries[] = [$uuid, $entityId, $name, $isSlim, $skinData];
+		$pk->entries[] = [$uuid, $entityId, $name, $skinName, $skinData];
 		Server::broadcastPacket($players === null ? $this->playerList : $players, $pk);
 	}
 
@@ -2280,7 +2280,7 @@ class Server{
 		$pk = new PlayerListPacket();
 		$pk->type = PlayerListPacket::TYPE_ADD;
 		foreach($this->playerList as $player){
-			$pk->entries[] = [$player->getUniqueId(), $player->getId(), $player->getDisplayName(), $player->isSkinSlim(), $player->getSkinData()];
+			$pk->entries[] = [$player->getUniqueId(), $player->getId(), $player->getDisplayName(), $player->getSkinName(), $player->getSkinData()];
 		}
 
 		$p->dataPacket($pk);
diff --git a/src/pocketmine/entity/Human.php b/src/pocketmine/entity/Human.php
index 34e15f785..08ccaba28 100644
--- a/src/pocketmine/entity/Human.php
+++ b/src/pocketmine/entity/Human.php
@@ -57,15 +57,15 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 	public $height = 1.8;
 	public $eyeHeight = 1.62;
 
+	protected $skinName;
 	protected $skin;
-	protected $isSlim = false;
 
 	public function getSkinData(){
 		return $this->skin;
 	}
 
-	public function isSkinSlim(){
-		return $this->isSlim;
+	public function getSkinName(){
+		return $this->skinName;
 	}
 
 	/**
@@ -84,11 +84,11 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 
 	/**
 	 * @param string $str
-	 * @param bool   $isSlim
+	 * @param string $skinName
 	 */
-	public function setSkin($str, $isSlim = false){
+	public function setSkin($str, $skinName){
 		$this->skin = $str;
-		$this->isSlim = (bool) $isSlim;
+		$this->skinName = $skinName;
 	}
 
 	public function getInventory(){
@@ -112,7 +112,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 			}
 
 			if(isset($this->namedtag->Skin) and $this->namedtag->Skin instanceof Compound){
-				$this->setSkin($this->namedtag->Skin["Data"], $this->namedtag->Skin["Slim"] > 0);
+				$this->setSkin($this->namedtag->Skin["Data"], $this->namedtag->Skin["Name"]);
 			}
 
 			$this->uuid = UUID::fromData($this->getId(), $this->getSkinData(), $this->getNameTag());
@@ -195,7 +195,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 		if(strlen($this->getSkinData()) > 0){
 			$this->namedtag->Skin = new Compound("Skin", [
 				"Data" => new String("Data", $this->getSkinData()),
-				"Slim" => new Byte("Slim", $this->isSkinSlim() ? 1 : 0)
+				"Name" => new String("Name", $this->getSkinName())
 			]);
 		}
 	}
@@ -210,7 +210,7 @@ class Human extends Creature implements ProjectileSource, InventoryHolder{
 
 
 			if(!($this instanceof Player)){
-				$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getName(), $this->isSlim, $this->skin, [$player]);
+				$this->server->updatePlayerListData($this->getUniqueId(), $this->getId(), $this->getName(), $this->skinName, $this->skin, [$player]);
 			}
 
 			$pk = new AddPlayerPacket();
diff --git a/src/pocketmine/network/protocol/LoginPacket.php b/src/pocketmine/network/protocol/LoginPacket.php
index 921b7ef03..6b8079f19 100644
--- a/src/pocketmine/network/protocol/LoginPacket.php
+++ b/src/pocketmine/network/protocol/LoginPacket.php
@@ -36,7 +36,7 @@ class LoginPacket extends DataPacket{
 	public $serverAddress;
 	public $clientSecret;
 
-	public $slim = false;
+	public $skinName;
 	public $skin = null;
 
 	public function decode(){
@@ -52,8 +52,7 @@ class LoginPacket extends DataPacket{
 		$this->serverAddress = $this->getString();
 		$this->clientSecret = $this->getString();
 
-		$this->slim = $this->getByte() > 0;
-		$this->getByte(); // TODO: skin transparency, experimental or not?
+		$this->skinName = $this->getString();
 		$this->skin = $this->getString();
 	}
 
diff --git a/src/pocketmine/network/protocol/PlayerListPacket.php b/src/pocketmine/network/protocol/PlayerListPacket.php
index 4ec5e4476..c9f65a664 100644
--- a/src/pocketmine/network/protocol/PlayerListPacket.php
+++ b/src/pocketmine/network/protocol/PlayerListPacket.php
@@ -53,8 +53,7 @@ class PlayerListPacket extends DataPacket{
 				$this->putUUID($d[0]);
 				$this->putLong($d[1]);
 				$this->putString($d[2]);
-				$this->putByte($d[3] ? 1 : 0);
-				$this->putByte(0); // TODO: skin transparency, experimental or not?
+				$this->putString($d[3]);
 				$this->putString($d[4]);
 			}else{
 				$this->putUUID($d[0]);