diff --git a/src/pocketmine/permission/Permissible.php b/src/pocketmine/permission/Permissible.php
index 777337fb8..7b59a2ac0 100644
--- a/src/pocketmine/permission/Permissible.php
+++ b/src/pocketmine/permission/Permissible.php
@@ -66,7 +66,6 @@ interface Permissible extends ServerOperator{
 	public function recalculatePermissions();
 
 	/**
-	 * TODO: Check this
 	 * @return Permission[]
 	 */
 	public function getEffectivePermissions();
diff --git a/src/pocketmine/permission/PermissionAttachment.php b/src/pocketmine/permission/PermissionAttachment.php
index be5eb80e4..585afbcda 100644
--- a/src/pocketmine/permission/PermissionAttachment.php
+++ b/src/pocketmine/permission/PermissionAttachment.php
@@ -88,17 +88,34 @@ class PermissionAttachment{
 		return $this->permissions;
 	}
 
+	/**
+	 * @return bool[]
+	 */
+	public function clearPermissions(){
+		$this->permissions = [];
+		$this->permissible->recalculatePermissions();
+	}
+
 	/**
 	 * @param bool[] $permissions
 	 */
 	public function setPermissions(array $permissions){
-		$this->permissions = [];
 		foreach($permissions as $key => $value){
 			$this->permissions[$key] = (bool) $value;
 		}
 		$this->permissible->recalculatePermissions();
 	}
 
+	/**
+	 * @param string[] $permissions
+	 */
+	public function unsetPermissions(array $permissions){
+		foreach($permissions as $node){
+			unset($this->permissions[$node]);
+		}
+		$this->permissible->recalculatePermissions();
+	}
+
 	/**
 	 * @param string|Permission $name
 	 * @param bool              $value