Your Character vs...WHO?

He loses in a straight up fight without tricks or illusions. He probably wins 10-15% if he can build up enough music empowerment, but she routinely goes against Wonder Woman so that's not likely.

YC vs Omni-Man

Major loss, I couldn't keep up with him!

YC vs The Royal Flush Gang

Their teamwork is too good, Mephisto loses

YC vs M.O.D.O.K.

From what I understand about him, I'd win in a good fight

YC vs Beast Boy

That's an easy win for Beast Boy, dude is a menace

YC vs Captain Britain

I'd like to say I could take 4/10

YC vs Brainiac

Hard loss.

YC vs Savage Dragon

It would be a good fight, but from what I think I know about him, Stomp wins 7/10

YC vs Wolverine (Logan)

Wolverine's healing hacks carry him through anything Mephisto can realistically do, hard loss.

YC vs Colossus.

Could go either way,

YC vs Wonder Woman

Megabyte can't do anything to her, hard loss.

YC vs Megamind!

In the end I'd get my hands on him, and then it's over!

YC vs Killer Croc and Man-Bat

Okay, that's a bit more interesting. It really depends on the versions of these characters. If Man-Bat is basically feral, he'd be easy to take out with illusions. If he has his refined serum then he'd more than likely understand what's happening and figure a way out sooner rather than later.

Killer Croc is very intelligent and, depending on their level of communication, would be instrumental in helping Langstrom find out the trick to Mephisto's deceptions.

Mephisto's best shot would be to isolate them from each other and maintain his lies as best he can... but that'd be quite the strain.

At best I can see him winning maybe 70% of the time if Man-Bat is feral, 30% if he isn't.

YC vs Wolverine and Colossus

It would be a good long fight that I would take the majority.

YC vs (CW) Supergirl

Mephisto would probably take the lead, but once she gets the hang of things he crumbles really quickly.

He loses!

YC vs Metamorpho!

He would win unless I got lucky enough to hit him with my acidic attack.

YC vs John Wick

John Wick has so much plot armor it's practically a power.

If Megabyte doesn't go for the kill immediately, he's done. Knowing him, he's stupid enough to give Wick plenty of time to figure out his weaknesses.

John wins, 9/10

YC vs Super-Skrull

I'd lose

YC vs G'Nort

A fight against any Green Lantern is an easy loss for Mephisto.

YC vs Judge Dredd

50/50

YC vs Vampirella

40/60 in her Favor

TC vs Robocop

I could take him in a good fight.

YC vs Parasite

Not a chance.

YC vs Catwoman

I'd win easily.

YC Vs Storm

Storm stomps hard.

YC vs Punisher