diff --git a/src/pocketmine/network/mcpe/protocol/RiderJumpPacket.php b/src/pocketmine/network/mcpe/protocol/RiderJumpPacket.php
index 802ba1ccf..3ee83a606 100644
--- a/src/pocketmine/network/mcpe/protocol/RiderJumpPacket.php
+++ b/src/pocketmine/network/mcpe/protocol/RiderJumpPacket.php
@@ -33,14 +33,14 @@ class RiderJumpPacket extends DataPacket{
 	public const NETWORK_ID = ProtocolInfo::RIDER_JUMP_PACKET;
 
 	/** @var int */
-	public $unknown;
+	public $jumpStrength; //percentage
 
 	protected function decodePayload(){
-		$this->unknown = $this->getVarInt();
+		$this->jumpStrength = $this->getVarInt();
 	}
 
 	protected function encodePayload(){
-		$this->putVarInt($this->unknown);
+		$this->putVarInt($this->jumpStrength);
 	}
 
 	public function handle(NetworkSession $session) : bool{
diff --git a/src/pocketmine/network/mcpe/protocol/ShowStoreOfferPacket.php b/src/pocketmine/network/mcpe/protocol/ShowStoreOfferPacket.php
index 92b392e95..a3f5a22c3 100644
--- a/src/pocketmine/network/mcpe/protocol/ShowStoreOfferPacket.php
+++ b/src/pocketmine/network/mcpe/protocol/ShowStoreOfferPacket.php
@@ -33,16 +33,16 @@ class ShowStoreOfferPacket extends DataPacket{
 	/** @var string */
 	public $offerId;
 	/** @var bool */
-	public $unknownBool;
+	public $showAll;
 
 	protected function decodePayload(){
 		$this->offerId = $this->getString();
-		$this->unknownBool = $this->getBool();
+		$this->showAll = $this->getBool();
 	}
 
 	protected function encodePayload(){
 		$this->putString($this->offerId);
-		$this->putBool($this->unknownBool);
+		$this->putBool($this->showAll);
 	}
 
 	public function handle(NetworkSession $session) : bool{
diff --git a/src/pocketmine/network/mcpe/protocol/StartGamePacket.php b/src/pocketmine/network/mcpe/protocol/StartGamePacket.php
index f7ee2b280..8a29d7b7f 100644
--- a/src/pocketmine/network/mcpe/protocol/StartGamePacket.php
+++ b/src/pocketmine/network/mcpe/protocol/StartGamePacket.php
@@ -112,9 +112,9 @@ class StartGamePacket extends DataPacket{
 	/** @var string */
 	public $premiumWorldTemplateId = "";
 	/** @var bool */
-	public $unknownBool = false;
+	public $isTrial = false;
 	/** @var int */
-	public $currentTick = 0;
+	public $currentTick = 0; //only used if isTrial is true
 	/** @var int */
 	public $enchantmentSeed = 0;
 
@@ -159,7 +159,7 @@ class StartGamePacket extends DataPacket{
 		$this->levelId = $this->getString();
 		$this->worldName = $this->getString();
 		$this->premiumWorldTemplateId = $this->getString();
-		$this->unknownBool = $this->getBool();
+		$this->isTrial = $this->getBool();
 		$this->currentTick = $this->getLLong();
 
 		$this->enchantmentSeed = $this->getVarInt();
@@ -206,7 +206,7 @@ class StartGamePacket extends DataPacket{
 		$this->putString($this->levelId);
 		$this->putString($this->worldName);
 		$this->putString($this->premiumWorldTemplateId);
-		$this->putBool($this->unknownBool);
+		$this->putBool($this->isTrial);
 		$this->putLLong($this->currentTick);
 
 		$this->putVarInt($this->enchantmentSeed);
diff --git a/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php b/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
index caab97964..e31a8d17c 100644
--- a/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
+++ b/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
@@ -82,7 +82,7 @@ class NetworkInventoryAction{
 	/** @var int */
 	public $windowId = ContainerIds::NONE;
 	/** @var int */
-	public $unknown = 0;
+	public $sourceFlags = 0;
 	/** @var int */
 	public $inventorySlot;
 	/** @var Item */
@@ -102,7 +102,7 @@ class NetworkInventoryAction{
 				$this->windowId = $packet->getVarInt();
 				break;
 			case self::SOURCE_WORLD:
-				$this->unknown = $packet->getUnsignedVarInt();
+				$this->sourceFlags = $packet->getUnsignedVarInt();
 				break;
 			case self::SOURCE_CREATIVE:
 				break;
@@ -137,7 +137,7 @@ class NetworkInventoryAction{
 				$packet->putVarInt($this->windowId);
 				break;
 			case self::SOURCE_WORLD:
-				$packet->putUnsignedVarInt($this->unknown);
+				$packet->putUnsignedVarInt($this->sourceFlags);
 				break;
 			case self::SOURCE_CREATIVE:
 				break;