Next generation co-op action gaming from the makers of Half-Life, Portal, Team Fortress and Counter-Strike.
AI Director 2.0: Advanced technology dubbed The AI Director" drove L4D's unique gameplay customizing enemy population, effects, and music, based upon the players' performance. L4D 2 features The AI Director 2.0" which expands the Director's ability to customize level layout, world objects, weather, and lighting to reflect different times of day.
New melee weapons axe, chainsaw, frying pan, baseball bat allow you to get up close with the zombies
Four different survivors. New Story. New dialogue.
More game. On day one, L4D 2 features more co-operative campaigns, more campaigns and maps for the Versus game modes than L4D 1, plus support for Survival mode out of the box.
Stats, rankings, and awards system drives collaborative play