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This article is about the room in Luigi's Mansion 3. For the stage in Super Smash Bros. for Wii U and Super Smash Bros. Ultimate, see Coliseum (stage).
Not to be confused with Colosseum.
Floor Castle MacFrights

The Coliseum is a large arena located in Castle MacFrights in Luigi's Mansion 3. It is first seen from the Coliseum Balcony and is accessed from the door at the east end of the Coliseum Hallway. The boss battle with King MacFrights takes place here. The arena is pill-shaped and features five windows with wooden doors on them from which arrows come out. The stands are occupied by cardboard cut-outs of ghosts which cheer the king on and boo Luigi during the battle.