The even better news, is that it seems it will be coming with cross-platform multiplayer with Windows. Something the developer wasn't too sure about initially.
Ethan Lee, the one-man porting machine behind many Linux ports has been helping with it. Ethan strongly recommends you run it in terminal to help catch issues. There will likely be issues with broke file paths, graphical weirdness and probably networking issues. As usual, your mileage may vary and test at your own peril. Ethan does say, that testing will be "extremely helpful", so if you have a slow week ahead this could be something fun for you to do.
Be sure to read the full post on Steam here for the more in-depth answers about what to look out for.
About the game:
From the creators of Rogue Legacy comes a "true-cooperative" action RPG. FULL METAL FURIES puts an emphasis on team play with a unique combat system where everyone is important. Work together to defeat special enemies, string organics combos to deal massive damage, and save a wartorn world that is battling itself to extinction. Play on the couch or online with friends, and make it a party for up to four players! Or go solo in single-player, and show off your skills through a Pick 2 quick-switch system that retains all the nuances of multi-play.