Round One:
Seeking vengeance for the infrigement upon his name and likeness, Deathstroke decides to take out Deadpool once and for all. He stalks him from the rooftops, determined to make the kill as quick and painless as possible. He watches with disgust as the mercenary takes on job after job that should be Deathstroke's, running his mouth all the while. Eventually, Deathpool sees an opening while Wade Wilson is walking through the streets of New York City and chattering to no one in particular how he's the coolest guy of all time. Finally, Deathstroke pulls the trigger on his sniper rifle, putting a bullet into Deadpool's skull. Deadpool drops to the ground and doesn't move. Nonetheless, aware of his opponent's powerful healing factor, Deathstroke heads down to the streets with a pair of machetes, determined to make sure Wade doesn't get back up. Round One goes to Deathstroke.

Round Two:
Deathstroke gets down to street level to finish the job, only to discover that Deadpool is nowhere to be found. He checks the trail of blood leading away from the would-be assassination, only to see it trail off down an alley. Deadpool's incredible healing factor has naturally closed up the wound, and while there is a bullet embedded in his brain, that shouldn't do anything but make him a little crazier than usual. Once Deathstroke is alone in the alley, he hears a cry of, "Hey Abbott!", followed up with a flying kick to the head. The attacker is, naturally, Deadpool, who assaults Deathstroke with deadly attacks and terrible puns. Deathstroke is brought to his physical and mental limits from having to ward off Wade Wilson's attacks while also trying to comprehend how someone can be so in love with the sound of his own voice. Round Two goes to Deadpool.

Round Three:
One Deathstroke recovers from his initial surprise, the fight becomes more even, with each combatant equally skilled in hand to hand battle. The one balancing factor is that Deadpool just won't shut up. The ranting goes something like this (quote from Cable and Deadpool -- an excellent comic with lousy covers):

"When I was a kid, I had a whole buncha GI Joes -- and I'm talking original plastic-hair ones, not the fuzzy-hair kung-fu grip guys -- or those little pansy tiny ones with the funny names and the cartoon -- a cartoon?! Plastic-hair Joe would roll over in his grave...if he could roll over...I sort of pulled his arms and legs off...then blew him up with an M-80...before I buried him in a shoe box with my hamster, Jolly Nuts...better not to ask...man, that M-80 blew Joe up but good..."

Driven to the edge of sanity by the merc with a mouth, Deahstroke starts yelling, "Shut up, shut up, shut up!!!" while laying into Deadpool with all the martial power he can muster. Unfortunately, his attacks seem to be all for naught...it's like he's fighting a loud-mouthed clone of himself. Ultimately, Deathstroke realizes that there's only one way to escape Deadpool's yammering. He takes out his emergency pistol, puts it to his head, and ends his misery.