Natural Selection 2 is the sequel to the popular Half-Life mod Natural Selection. It is built on our own engine and will be distributed through Valve's Steam platform.
I absolutely adore this game. So yes, I am definitely biased.
It has all the things which make a team based shooter fun - ie: teamwork, guns. But then it gives us asymmetric sides, so it's guns vs. teeth, claws, arm spikes. This leads to tense confrontations between spinning, careening packs of aliens and their ill-protected, rifle armed prey.
But then on top of the fun of individual encounters, on top of listening as aliens skitter through the ventilation systems, on top of waiting for the perfect moment to appear and tear marines to shreds, there is an entertaining meta-game.
The team's commander views the battle like an RTS, building and researching, instructing the rest of the team of the current state of the game and ordering them to do specific things. An overall strategy usually quickly emerges, around which the team unites. The goal, however, is always the same: Destroy the Enemy's Command Structure - A Hive for aliens, a Command Chair for marines.
The to-and-fro of battle makes for surprisingly cerebral games, with a Comm deciding that the team must control some rooms but being willing to give up a few others. Deciding where and when to drop a second base. "Shotguns or Proximity Mines first?" "Is anyone here a good fade? Yes? Researching Blink." "Onos in spawn! Onos in SPAWN! ONOSINSPAAAAAWN!"
A smart shooter.