Goomboss

Goomboss (Originally named the Goomba King) is a boss in Super Mario 64 DS. They are a large Goomba with a mustache, eyebrows, clothing and a crown. They are found in the Goomboss Battle level, and unlock Mario when defeated.

They are mainly fought with Yoshi. They run around their circular arena, and do damage upon contact. To defeat Goomboss, the player has to throw eggs at them 3 times. The eggs can be acquired from the Goombas that follow Goomboss around. Each time Goomboss is hit, they grow bigger and run faster.

Super Mario 64 Manifestation
Goomboss, along with Goomboss Battle, has been reported to appear in some personalized copies of Super Mario 64. They usually function the same, though they usually need to be punched or jumped on instead of being hit with eggs due to most personalized copies only having a playable Mario. When defeated, they usually drop a star, or a key unlocking a floor of the castle.