Six months ago, Ryan Reynolds told MTV News he would "forgo anything" to play the "X-Men" character Deadpool "in some incarnation."

So what did he have to sacrifice? Story rights? Back-end gross? Another film? None of the above. In the end, all Reynolds had to give up was top billing.

Reynolds will cameo as Wade Wilson, the sarcastic "Merc With a Mouth," in the upcoming "X-Men Origins: Wolverine," reported AintItCoolNews. And the 31-year-old actor couldn't be more excited. "I've always wanted to do Deadpool," Reynolds enthused.

Black Eyed Peas rapper/producer Will.I.Am has also been added to the spinoff's cast, as John Wraith, a.k.a. Kestrel. The flick will be the MC's first, but he does have guest-starring roles on the TV shows "Cane" and "Joan of Arcadia" under his belt.

As for Reynolds, the small film appearance seems a perfect way to introduce the acerbic character to larger audiences while also appeasing more hard-core comic enthusiasts, particularly due to the difficulty in otherwise introducing the character for a solo film.

"It's a very tricky character to do. It's ambiguous whether he's good or bad. He's a mercenary. This is all to say nothing of the fact that his face is made entirely of scar tissue," Reynolds sighed back in August. "These are huge issues."

Huge issues that, in some ways, present themselves with Wolverine as well. That's no coincidence, Reynolds explained.

"[Deadpool is] a derivative of the Weapon X program," the same program Wolverine went through, Reynolds said. "They turned him into a puddle and shipped him off. Just left him for dead. But he came back with all these mutant powers. And he's pissed off — in a full-fledged, I'm-gonna-get-you way."

The first of several planned "X-Men Origins" films, "Wolverine" is fast becoming a mutant extravaganza. In addition to Deadpool, the film will also have a cameo from the Blob, a supersize mutant able to create his own gravitational field, according to FilmSchoolRejects. Finally, long rumored to be up for an appearance in each of the previous three "X-Men" flicks, Gambit will appear in "Wolverine," reported SuperHeroHype. He will be played by "Friday Night Lights" star Taylor Kitsch.

Gambit and the Blob join a group of already-confirmed mutants including Wolverine's love interest Silver Fox ("The Number 23" star Lynn Collins) and Sabretooth (Liev Schreiber).

Positioning characters in crossover roles, as cameos or setups, is fast becoming a habit for Marvel Studios, which only recently gained final editorial control on many of its properties. Sam Jackson will appear as Nick Fury in "Iron Man," for instance, while Iron Man himself, Tony Stark (Robert Downey Jr.), will appear in "The Incredible Hulk."

Directed by Oscar winner Gavin Hood, "Wolverine" is currently filming and will open May 1, 2009.

The Academy Awards are this weekend, and MTV News will be on the red carpet with a live pre-show on Movies.MTV — we'll also have tons of photos, video and, of course, a full report on the show, the fashion, the stars and much more! Be sure to check it out on Sunday, February 24, beginning at 7 p.m. ET on Movies.MTV!

Check out everything we've got on "X-Men Origins: Wolverine."

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[This story was originally published at 5:51 pm E.T. on 2.19.2008]