It's a meeting of minds so anticipated, they could have put it on pay-per-view.
Prepare for a play-by-play…
"My movie's about vampires. Yours is about wizards, so my movie is less stupid basically," (Fallon as) Edward Cullen says.
"You get to cast spells in my movies. Here's a spell for Robert Pattinson: Twilighticus suckus!" (Fallon as) Potter declares.
Yeesh! Then things get personal.
"I sparkle in the sunlight. It's dazzling," the vampire boasts from his tree-top perch.
"Your skin sparkles in the sunlight. I mean, it looks like something Elton John would wear for an encore!"
"I'm 6-foot-1, Radcliffe is 5-foot-6. Do the math. Sex symbol. Boom!"
"He's taller than I am. Hey, Pattinson, I make more money! Scoreboardicus," Potter hexes, finishing the vamp off with, "He's greasy and he's smelly-looking. Very smelly-looking."
Game, set, match. Fallon wins.
Care to continue the battle? Write your own face-off script in the comments!
While you're at it, have you decided yet if you prefer Pattinson or Taylor Lautner's Interview photos?