Pet Battles are a great way to challenge your friends (and enemies!) to a game of strategy and tactics with unique abilities and exotic creatures. Not to be confused with tamed pets, Pet Battle Creatures are pokemon-esque minions that only exist within the confines of Pet Battle Arenas. Pet Battle creatures are summoned upon the initiation of a Pet Battle match between players and they don't require taming skill to command them.
For those unfamiliar with this system, two players face each other in an arena-esque type setting, yet instead of going head to head with swords and magic, they send their pets to fight to the death in order to bring great honor and wealth to their master.
Read about the system here Wiki