New Mob: Blackbolt

A fast and black primate-looking mob called a blackbolt that is extremely rare and only found in small cages of bastions in the Nether. Players must be cautious when opening the cage as the blackbolt runs incredibly fast. 

Players must find a baby variant of this mob and feed it an enchanted golden apple to tame it. 

Once tamed, it sits on the player's shoulder, never grows up, and gives the player a permanent swiftness effect until it is released off the shoulder. The benefit of the mob can also be changed and balanced accordingly.