What is how to evolve gimmighoul?

To evolve Gimmighoul into Gholdengo, you need to collect 999 Gimmighoul Coins. These coins can be found by interacting with Roaming Form Gimmighoul and Chest Form Gimmighoul scattered throughout the Paldea region, as well as from Tera Raid Battles.

Once you have 999 Gimmighoul Coins, leveling up your Gimmighoul will trigger its evolution into Gholdengo. You do not need to trade Gimmighoul while holding the coins. The coins simply need to be in your inventory when Gimmighoul levels up.