Imaginarium Theater is unlocked by completing the World Quest Unbegun, Unending Story, unlocked after reaching AR 35. We did not list this World Quest as it takes place further in the story, but it shouldn’t have any spoilers. This quest unlocks the Imaginarium Theater gamemode.
Imaginarium Theater is an endgame mode that resets every once in a while, and it requires you to own a set amount of characters, and also requires them to be high leveled and properly built. Each cycle also forces you to use only certain elements. It’s intended for late-game players.
Inside the Theater, your character will appeear. Be careful as talking to them might come with spoilers.
Inside the Theather there’s a fortune slip stand. It may contain lore. If needed, the guide will handle it.