Team up? EggBrain hates Metal Sonic and considering we might wake up in heroes it means we might get hijacked.
Yeah, remember that Metal absorbs stuff in Heroes. Like, I'm pretty sure he got Cream's pet Chao, and Big's frog. Odds are, the first thing he'd do if we woke up to him would be to absorb
us. Which means we'd either have no agency, or wind up playing as one of Metal's subprocesses. And frankly, I don't like Metal (no kayfabe), so I don't want to play as him or anything working for him regardless of willingness.
Gamma I could accept; don't know what we'd be doing if we wind up working for him, but I could accept it. Tails I could reluctantly tolerate; I'm apathetic towards him IRL, but it just doesn't feel fitting to just randomly wake up as his subordinate here. Metal?
Not acceptable.
I guess but Metal sonic doesn't attack eggman in heroes mearly force him into hiding and then takes his place.
Actually, pretty sure he forcibly confines Eggman; that's the entire reason he gets the Chaotix involved- he's stuck in an empty room and needs someone to find him and bust him out so he can regain control of his empire.
It's also the most reasonable thing to do when you're going around impersonating someone; after all, if another one shows up, that'd be awfully inconvenient, wouldn't it?