Marvel vs. Capcom Origins is a game compilation of 2 of the most popular games of the 90's, which are Marvel Super Heroes and Marvel vs. Capcom: Clash of Super Heroes, that was released as a downloadable title on September 25, 2012 for Xbox Live Arcade and the PlayStation Network. It includes HD graphics and online multiplayer.
Marvel vs. Capcom Origins features Marvel vs. Capcom: Clash of Super Heroes as default and Marvel Super Heroes by pressing select. It features history facts about the Marvel vs. Capcom series and Marvel comics along with a vault that can be used to unlock stuff and challenges that can be used to level up.
While Anita was only playable in the Japanese version of Marvel Super Heroes, Anita is unlockable, along with Doctor Doom and Thanos.
Onslaught was playable in the PS1 version of Marvel vs. Capcom: Clash of Super Heroes, however he's not playable in Marvel vs. Capcom Origins, while Anita is playable in Marvel Super Heroes despite being only in the Japanese version.
Thano's ending has the arcade ending that has Magneto's dialogue instead of his own.
Mega Man can't use the Magnetic Shockwave in Marvel vs. Capcom Origins. This is most likely due to him only having the move in the PlayStation version of MvC1, and the version used in Origins is the Arcade version.