Pet Vex!! A controllable pet that can fight for the player

The pet vex is a new twist that would allow the player to have a controllable hostile pet!! 

The pet vex offers a new and unique way for the player to interact with the Minecraft world. The pet vex acts as an incentive for players to explore and search out woodland mansions. Finally, The pet vex continues a pattern hostile to friendly mobs started with the happy ghast.

To incorporate the pet vex into the Minecraft world, there would be a tool. The pet vex would be summoned by the player using a summoning rod. To get the summoning rod, the player will have to fight through and conquer The Woodland Mansion, with the rod or pieces of the rod being mansion rewards. 

Right click the rod and a vex will appear! Once summoned the rod is used to control the vex. Moving the crosshair over a mob and left clicking would send the vex to attack that mob. Holding the left click down for 3 seconds would set the vex into a patrol mode. Finally right clicking would make the vex disappear

While the vex fights, it should act just like a normal vex. Other players and hostile mobs would be able to kill the vex. If they kill the vex, the summoning rod would loose durability. To differentiate the vex from the wolf, the vex will not react to the player being hurt. The vex can act as a offensive pet, where as the wolf acts more as a defensive pet. 

The pet vex should be Minecraft's next mob because it expands upon an existing mob in the game and offers players a new way to interact with their worlds.