Bosses will appear in certain stages of Super Smash Bros.

Fighters will have to battle the boss, as well as fight each other. These bosses will allow for different strategies to be used to damage opponents.

One example shown in the Nintendo Direct, was the Yellow Devil boss in the Wily Castle stage. A vulnerable spot sits in the middle of its body, its eye. If players defeat the Yellow Devil, it starts to explode. The explosion becomes an attack for the player who delivers the final blow, engulfing anyone in the blast radius.

No other bosses were revealed, but Ridley was teased to be a boss in a Metroid stage called the Pyrosphere.