RaiderZ is an open world MMO with action based gameplay like Vindictus.
It’s in Alpha right now, but if you go apply to one of many websites giving away keys, then when Beta comes around, you get a very cool wolf mount.
http://www.curse.com/betas/raiderz = Purple Wolf
I’ve been playing the game, it has sort of an Open Class system, as far as i can tell. It’s very cool, even though it’s not finished yet. I highly recommend taking part in the Alpha, even if it is jsut so you get a cool mount in the Beta.