The VS Game

[MarvelFan12345]

Invisible Woman, but Iceman could also possibly win if he tried completely.
Firestar vs Justice

[Rogue]

Firestar

vs 

[LawO]

Probably Mystique, but I love Domino.

Havok vs. Hellion

[Midnightphoenix]

Hellion

Super Skrull vs Hulk

[Galactus]

hulk
jean grey vs toad xD

[LawO]

Obviously Toad XD Jean Grey 
Blink vs. Nightcrawler

[Nowhere Man]

Blink

Ironman and Invisible Woman vs Vision and Storm

[scott summers]

I believe vision and storm. If Ironman fires anything at vision, he will use his phase and storm could eletrocute him. Then vision uses his phasing ability again and sue's forcefields can't block him.

[Midnightphoenix]

Well you didn't post one XD

Magik vs Witchfire

[MarvelFan12345]

Magik
Moondragon vs Mantis

[Nowhere Man]

moondragon

Quentin Quire vs Rachel Grey

[MarvelFan12345]

Rachel
Revanche vs Madame Hydra/Viper

[Midnightphoenix]

Revanche

Viper vs Domino

[MarvelFan12345]

Domino
Jean Grey and Storm vs Sisterhood of Mutants

[MaritaG]

that's very tricky, because Jean has the same powers as madelyne... but i guess if Jean uses her full power vs the sisterhood well... Jean and Storm.

White Phoenix vs The Brotherhood of Mutants and the Sisterhood of mutans.