It’s idk, what it is. It’s a guard I think

Yes, I’m the great Pikachulibre12, a Pokémon who can’t be tamed!

Yeah, it’s one the legendary Pokémon, and it fights with Hoopa who summons them to fight each other, while arceus tries to get along with humans but keeps getting “trapped” by trainers to rule the world for its power. So arceus tries to destroy humanity and ash and Pikachu save the day.