Comparing it to TF2 is not that far away. They are pretty similar in style and gameplay. MNC is a smaller game (less maps, players, game modes, weapons and no hats) but that is to be expected from indie developer (vs. Valve). MNC has two game modes: either you play in same team and try to protect target from AI waves (that increase in difficulty). Other mode is human teams against each other trying to destroy the target but the catch is that both have AI bots helping them. Also, you get to customize your character a bit which has slight effect in your gameplay (e.g. more speed or health).

Personal opinion: not as good as TF2 but it has its place. Enter if you consider it worth 15p and the risk (probability might get close to 1/800).

Indeed it is, my friend. But when I think of it, every day is a good day to blow stuff up...