Sandstorm creates lots of explosions of drama without relying on scripted sequences. The AI, if you're playing in PvE, is more than competent, and you'll often find yourself holed up near an objective, nervously peering out of windows as you wait for the assault. Then everything goes to Hell and there's shouting and screaming and dying soldiers trying to crawl to safety.
The sound design is a high point, with allies and enemies chatting and barking away, and gunfire and explosions echoing down city streets. The dramatic shift from a deserted alley to a fire-drenched warzone is more than a bit jarring—just what you want for a lazy weekend inside.
Insurgency: Sandstorm is free on Steamuntil 10 am PT on June 24.