galacta knight
A recurring boss character in the Kirby series. He makes his debut in Kirby Super Star Ultra at the very end of the Meta Knightmare Ultra subgame, where Meta Knight summons Galactic Nova to wish for a fight against him. Since then, he has made various re-appearances as a secret superboss in future Kirby games (Kirby's Return to Dream Land, its remake and Kirby: Planet Robobot to be exact). In Kirby Star Allies, however, a "fluttery fiend" absorbs him and is fought instead.
He is the strongest warrior in the galaxy in Kirby's world and was sealed away because he was deemed too strong. (Star Dream even suggests that he may have destroyed at least one planet in the past).
He also appears in Super Kirby Clash as a true final boss, surprisingly enough. Here, he is dubbed "Aeon Hero", and counts with two powered-up forms -Light and Dark- that change his appearance. He is also implied to be one of the ancient heroes who sealed away Void Termina long ago, as he attacks using the spears of the heart that kept the Dark Lord in place.