King Golem is the boss of Moonlight Mansion.

Moonlight Mansion is a level featured in Kirby & the Amazing Mirror for the Game Boy Advance. It is the second stage featured in the title, and houses King Golem, the boss of the area who is assumed to actually be part of the castle. This is the first stage in which you'll obtain a mirror piece by beating a boss. The miniboss of the stage is Mr. Frosty. Various other enemies are found within as well, including: