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Boss Keys are items that appear in Donkey Kong 64. There are eight of them, and as its name implies, each one is guarded by a boss. The only Boss Key that is not guarded by a boss is the final one, which is located behind a steel door in K. Rool's throne room in Hideout Helm. Each Boss Key's purpose is to unlock a corresponding padlock on K. Lumsy's cage. Doing so causes K. Lumsy to boisterously celebrate, and he creates a tremor to cause an event to occur on DK Isles, usually opening previously-blocked entrances to other worlds. He is freed from his cage after the Kongs unlock all eight padlocks on his cage.