Suggested by Sonic King Boom Boo was always a fun villain from Sonic Adventure 2 Battle. He never quite captured the same level of hype and respect as King Boo but you couldn’t help but pull for the guy. He’s got a fun design but not a whole lot of offensive power. Etna would easily be able to crush him with pure power or she could use a bolt of magical power. Either way as a Demon Lord her abilities far outstrip Boom Boo’s. Etna wins.