This stage is from Kirby Super Star. In the sub-game Revenge of Meta Knight, Meta Knight attempts to take over Dream Land using an airship known as the Halberd. In order to stop Meta Knight, Kirby must infiltrate the airship and destroy it from the inside. The Halberd in Smash is loosely based on its appearance in Super Star, though it has a more streamlined design, which would become the basis of its design in later Kirby games.

Halberd Deck by Bonboon228

Halberd in the Sky by KenJou_Lirt