One of the characters that was most requested in this game (after Spider-Man, of course): Black Widow.

Natasha may not have the same strength as other characters, but she can stand firm in a variety of situations. It has several variations on its special main, which can be changed through the UP UP + A or DOWN DOWN + A command.

Avengers United Battle Force is a free #fanmade game done using the #openbor engine.
You can play it in #android #linux #windows and even in #retropie(needs some work)
Download for free here: http://www.brazilmugenteam.com/avengers