Legends: Arceus Pokedex

Open-world action RPG set in ancient Sinnoh (called Hisui). You catch Pokemon by throwing Poke Balls at them in the overworld without battling. No abilities, no held items. Battles use Agile Style (move first, less power) and Strong Style (more power, act later) instead of traditional turns. Alpha Pokemon roam as mini-bosses.

Oshawott evolves into Hisuian Samurott (Water/Dark), which is the most useful for the story. Rowlet's Hisuian Decidueye becomes Grass/Fighting. Cyndaquil's Hisuian Typhlosion (Fire/Ghost) has the most unique typing. All three work, but Oshawott's coverage is the most versatile.

Larger, more aggressive Pokemon that roam the overworld. They have red eyes, higher levels than surrounding Pokemon, and guaranteed perfect effort levels (the Legends: Arceus equivalent of EVs). Some Alphas are fixed spawns you can farm. They're the main source of high-stat Pokemon for your team.

Regional variants exclusive to the Hisui region. Hisuian Zoroark (Normal/Ghost) gets three immunities. Hisuian Typhlosion is Fire/Ghost. Hisuian Samurott is Water/Dark. Hisuian Lilligant (Grass/Fighting) and Hisuian Goodra (Steel/Dragon) are new typings. Some Hisuian forms also have new evolutions not found in other games.

Gen 8 by release timing, though it plays nothing like a Gen 8 game. Switch, January 2022. Game Freak built it as a prequel to Diamond and Pearl set in ancient Sinnoh (Hisui). Action RPG mechanics replaced the traditional turn-based formula.