Castle Dedede is a location owned by King Dedede that appears in some The Subspace Emissary cutscenes in Super Smash Bros. Brawl. King Dedede kept three trophies here: Luigi, Ness, and either Princess Peach or Princess Zelda (depending on which character was played as). After he puts a badge on the three of them, the roof of the castle starts falling. A piece of the roof lands on King Dedede's head and knocks him unconscious. It is then shown that the roof was destroyed by Bowser and his Koopa Troop, who then hop in the castle, take the princess trophy and rush out.
Minutes later, the Ancient Minister flies in here and his R.O.B.s set up a Subspace Bomb, which explodes then swallows a large part of the castle. The Luigi, Ness and King Dedede trophies manage to survive. Later, near the end of the game, they are found very near Castle Dedede.