Pokemon Legends: Arceus - How To Catch Arceus

thegamer.com:

Pokemon Legends: Arceus takes you back in time to the ancient region of Hisui, where you will become a member of the Galaxy Team. As part of the Survey Corps, yours is the task of completing the Pokedex, which also seems to align with the circumstances that took you to this mysterious region in the first place.

Related: Pokemon Legends: Arceus - How To Raise FriendshipEquipped with the enigmatic Arc Phone, you will receive ominous messages that compel you to complete the encyclopedia, to meet the one responsible for your current situation. This will take you to numerous zones, fighting both common, uncommon, and even legendary pokemon, so you can reveal the final mystery in this game.

At the end of your journey, Arceus awaits.

Known as "the heavenly fount from which pours the light that shines across Hisui", Arceus is a cosmic being that it's believed to be the creator of all things. Officially introduced in the fourth generation games, Arceus was intended to appear in Pokémon Diamond, Pearl, and Platinum by using an event item called the Azure Flute. However, this item was never distributed, thus becoming obtainable only by a Mystery Gift. Since then, Arceus has been distributed as a Mystery Gift numerous times across the later generations of pokemon games, finally getting the spotlight in Legends: Arceus.

To find Arceus, you must first finish the main story, and the post-game story as well. After you successfully defeat Volo, a new cutscene will show up, where your flute will become the fabled Azure Flute, and your Arc Phone will tell you to go and capture every pokemon, once again. The final Main Mission, called "The Deified Pokemon", will then begin.

Now, as you may have noticed, if you go to the summit and play the