Kolossos (as seen in Outcome Memories)
Sonic the Hedgehog's corpse, possessed by a brutish demon. Now they have a fleshy spike for a right arm, and they're the only Executioner that can block being hit by a survivor's ability. Plus, when he starts charging in-game, he's seen being able to charge faster than even *Sonic* can run in OM.
Mystic Flour Cookie (Cookie Run universe)
The amount of apathy she's able to cause a cookie to take in can & would literally cause said cookie to turn back into flour because they completely lost the will to live. Even though I'm a human, the apathy she would cause me to take in would probably make me give up on the fight and cause me to just "Hold X: Coward's way out", if you get what I mean.
Bowser (Super Mario universe)
Not only has he been able to fight Mario all these years, but he's a bipedal tortoise with spikes on his shell, he's able to breathe fire *and* spit fireballs, he came back from death at least 20 or so times, he's able to utilize transformations just like the playable Super Mario characters. I could keep going on about him.
Peppino (Pizza Tower)
He can parry attacks by *taunting* the second he's hit, he caused an entire tower to collapse by suplexing Pizza Head into the top of it, he can break through steel boxes by going fast enough, and he can reach running speeds of 73 MPH, if we use realistic measurements. For scale reference, a fully upgraded Vapid Minivan in GTA V can reach a top speed of 95.25 MPH (153.29 km/h).
Juggernaut (the enemy from the CoD: MW2 campaign)
They can endure at least 3 shots from a grenade launcher or RPG in terms of health, they lug around an LMG that does as much damage to me as it would to somebody in Multiplayer, and they somehow have infinite ammo for their LMG as well.