Celebrating the pre-Halloween weekend, Left 4 Dead 2 will be free on Steam this weekend. Valve announced that starting Thursday the co-op shooter will be gratis to play and is currently available to pre-load.

This weekend adds a new achievement titled "Good Guy Nick" for current players who join up with a free weekend warrior.

It should also be mentioned, in case you haven't paid attention the multi-million selling franchise in a while, that Left 4 Dead 2 added many of the maps from the original Left 4 Dead as free DLC on PC a while back.

[Thanks, Bean]

This article was originally published on Joystiq.