Trying this out, pretty cool and its F2P. Not sure I totally get it all yet, but its very FPS oriented, but its a bit more complicated than the typical run and gun, with 3 factions and big beautiful maps with huge battles going on that never end.... And it has a RPG/MMO type upgrade system of some sort... Tanks & aircraft.

Available on Steam for free.

I'm playing the Vanu Sovereignty faction on the Waterson server.