The Hisui region is a fictional area in the Pokémon universe, introduced in the game Pokémon Legends: Arceus. It is based on the real-world Hokkaido region of Japan and features a variety of landscapes, including mountains, forests, and lakes. The Hisui region is set in the past, during a time when humans and Pokémon were still learning to coexist. In the Hisui region, players can explore different biomes and encounter unique Pokémon, some of which are regional variants of existing species. The region is also home to the ancient Sinnoh civilization, which plays a significant role in the game's storyline and lore.