Altarium is an atmospheric horror adventure game that offers both PvP and co-op gameplay for 1-5 players. Set in the mysterious city of Golden Horn, the game follows a team of bounty hunters sent to retrieve the powerful Jewel of Corion, only to find themselves trapped and pursued by its keeper. Players can either join the desperate team of explorers Team A, consisting of Hannah Falkenhorst, Black Jack Kane, Grimruth, and Marco Rocio, or play as Luxazul, the fearsome keeper of the jewel.