There used to be a game like this, a free to play FPS MOBA, Land of Chaos Online (LOCO). Had played the shit out of it. It was awesome fun. Just the number of people playing was very less. Watching videos of this game reminds me of it. Issue with FPS moba's is their novelty doesn't last long and the long time appeal is rarely there. There is not real strategies that needs to be evolved and adapted as the game changes, no in-depth strategy analysis ... nothing like that to keep the game going. Time spent on this might be better spent elsewhere. (just my opinion based on what gameplay videos i have seen).