Mr Mxyzptlk is back, but he won’t be able to stop Deadpool! Deadpool has his healing factor and his guns at the ready. Mr Mxyzptlk will have a hard time trying to deal with all of that. He definitely likes making tricks, but Deadpool always manages to get the last laugh. Deadpool wins.
Update! As of 07/11/2016 It has been pointed out that Mr. Mxyzptlk aqctually has had some decent moments and feats in the comics with serious firepower. I don’t think Deadpool will be able to keep up with this guy. Mr. Mxyzptlk wins.
DReager1.com 
http://s238.photobucket.com/user/Galan_photos/media/wf14.jpg.html
https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcSvIjbLzmjf5j5q4ymqE46eTpflbhkV0OsY_vXlUSPQkviWjbOc7Q
This is actually not a bad feat. With this kind of power, Mxy would beat Deadpool.
That actually wasn’t bad and when you also consider the story about whatever happened to Superman, I think he does have the match. Consider this round overturned.
Who would be dumb enough to think that Mr.Mxyzptlk would lose to Deadpool.
Me….
Deadpool can go talk to the writer and maybe threaten him but can Mr. Mxy stop him from doing it so?
That’s a tough one. Once you start breaking the 4th wall there’s not much you can’t do