Even though the game is old, one of the best team vs team games I've played. There's nothing quite like it in the wild among new games. Not a single one required so much team coordination to actually pull the victory and it's very punishing if either your commander fails to provide support and guidance or the regular players fail to defend/attack a crucial objectives. Both sides (Marines and Kharaa) are extremely different in gameplay and can satisfy almost any player in what different roles can offer (especially on the alien side, as there you can literally play as either: ambusher, support, tank, assassin or just not care and go straight into enemies' face with a good ol' skulk considering the speed they can go at). Would love to see a continuation but most likely it will not happen.

Helldivers

One of the best games. Nothing like it.