Shingeki no Smash Bros.

Solid Snake as Mikasa Ackerman.
Zelda/Sheik as Armin Arlert.
Pit as Levi's squad.
Mewtwo as Titan Eren.
WiiFit Trainer as the Female Titan.
Everything is spot-on.

And most importantly, Rockman as Erwin Smith looks boss!

Props to DeviantArt user AmazingArtistYellow for this awesomely done, hand-drawn animated parody/tribute to Super Smash Bros. and Shingeki no Kyojin.