It’s still not to late to claim this free game. Insurgency, a team-based millitary shooter, is free right now on Steam. Just go here, log in and click on “Install Game”.
First released in 2007 as a mod using the Source Engine, Insurgency was released as its standalone game in 2014. A sequel to this, Insurgency Sandstorm, will be released later this September.
If you are interested in a realistic shooter to play with friends, go grab it now while it is still available.