The story starts with a scene where Steven is teaching you about battling

with a Pokémon. When you finish learning, you are asked to choose one

Pokémon from the three Sinnoh starters.

Then, you will have to defeat Gym Leaders, collect Badges and so on until

you met Team Hunter, a team that are lead by sixteen Trainers known

as Chaos Sixteenth. They try to collect Plates from legendary Pokémon

to summon the God of the Pokémon, Arceus...