Big Bob-omb

Big Bob-omb, later to be renamed as King Bob-omb in future installments, is a boss in Super Mario 64 and ruler of the Bob-ombs. Residing atop the mountain in Bob-omb Battlefield, he is the first boss players will come across, and he appears in the star; BIG BOB OMB ON THE SUMMIT. He must be defeated by picking him up from behind and throwing him onto the ground.

Appearance
Big Bob-omb is a large bipedal Bob-omb with purple arms and legs and yellow extremities. Big Bob-omb has a large crown and white mustache. Similar to the Bob-omb buddies, Big Bob-omb does not have a fuse and only explodes when defeated.

The Big Dud
The Big Dud refers to a minor detail in Super Mario 64 relating to the boss enemy Big Bob-Omb. After Big Bob-omb is defeated, Mario can talk to one of the Bob-omb Buddies in the start of the level who tells him that: "Big Bob-omb is nothing more than a dud now". This is seemingly related to the spheres at the base of the mountain in Bob-omb Battlefield.

There are two Big Steelys at the base of the mountain; however after Big Bob-omb is is defeated one extra Big Steely appears at the base of the mountain. Taking into consideration that Big Bob-omb became a "dud" after his defeat, this implies that the third Big Steely at the base of the mountain is actually Big Bob-omb. Considering that the Big Steelys at the base of the mountain are not launched from a cannon like the other Big Steelys, the two original Big Steelys at the base of the mountain could be earlier generations of Big Bob-omb. This could mean that two earlier generations of Big Bob-ombs were defeated and became "Big Duds".

It is worth noting that Big Bob-omb explodes after he is defeated, so it's possible that the extra Big Steely at the base of the mountain might not be Big Bob-omb's body. However, this might be an intentional simplification since creating a cutscene where Big Bob-omb rolls down the mountain might accidentally draw the player's attention to where he went rather than the star he drops.