The Legendary Marvel Comics Art of Marvel vs. Capcom 2, Like You've Never Seen It Before
Why were these games previously unavailable for purchase?

The games were previously unavailable for purchase due to rights issues. The collection includes seven iconic crossover games between Marvel and Capcom, and getting the rights to make these games available again was a complex process.
What games are included in the Marvel vs. Capcom Fighting Collection?

The Marvel vs. Capcom Fighting Collection: Arcade Classics includes seven games: X-Men: Children of the Atom, Marvel Super-Heroes, X-Men Vs5. Street Fighter, Marvel Super-Heroes Vs. Street Fighter, Marvel Vs. Capcom: Clash of the Super Heroes, Marvel Vs. Capcom 2: New Age of Heroes, and The Punisher.
What extra features does the collection offer?

The Marvel vs. Capcom Fighting Collection offers an art gallery with high-resolution concept art and promotional character work developed by Capcom for each game, including never-before-seen details. It also features high-resolution versions of character illustrations for all 56 Marvel and Capcom characters in Marvel vs. Capcom 2 by the legendary Japanese artist Bengus.