Hi @A12Savage, Keys of Light/Night and the mimics they spawn do not exist on Xbox 360. They are part of the 1.3 update which Xbox 360 will not receive due to system limitations. Are you trying to spawn regular mimics, or the big Hallow/Corruption/Crimson mimics? Regular mimics cannot be made to spawn, they just spawn naturally in the world. The big biome mimics need Keys of Light/Night and are not on the 360.
