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. Atop the mountain and as the first star in Bob-omb Battlefield, he is the first boss many players will come across. He must be defeated by picking him up from behind and throwing him onto the ground.

The Big Dud
The Big Dud refers to a minor detail in Super Mario 64 after Big Bob-omb is defeated in the first mission. In the second mission, Mario can talk to one of the Bob-omb Buddies in the start of the level. There, the Bob-omb Buddy mentions that Big Bob-omb is "nothing more than a dud now". In the first mission of Bob-omb Battlefield, there are two rolling metal spheres at the base of the mountain behind the metal fence. However in the second, there are three rolling metal spheres instead of two. Taking into consideration that Big Bob-omb became a "dud" after his defeat in the first mission, this implies that the two metal spheres at the base of the mountain are actually earlier generations of Big Bob-omb. This can mean two things: The plot of Super Mario 64 has happened twice already in the game's lore and that Mario has defeated earlier generations of Big Bob-omb two times in a row, or that the war in Bob-omb Battlefield has already been won two times by the Bob-omb Buddies by the time the game starts. This is a minor detail that implies a unusually high amount of lore for a Super Mario Bros game which is a bit bizarre.

It is worth noting that Big Bob-omb explodes after he is defeated, so it's possible that the extra metal sphere 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.