Suggested by Destroyer Bob Ombs have powerful explosives so you don’t want to count them out but this is a rough matchup for him. Boo can turn intangible and so that nullifies the Bob Omb’s greatest ability. I see Boo just charging in and landing blows at will while Bob Omb has a noticeable lead up to the actual explosion that can be easily dodged. Boo wins.
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Boo wins this one easily and Its not even close! Here is a Video of boo literally easily beating 30+ Bob-ombs while also having to avoid Mecha Bowser’s fire and bullet bill attacks and end’s up defeating Mecha Bowser Himself along with the 30+ bob-ombs! Boo wins beyond negative Difficulty! 🙂 Here is the link: https://www.youtube.com/watch?v=LQmqujg3ueI