Valve is making the prospect of picking up Left 4 Dead real hard to pass up this weekend, as the company announced today that its free weekend promotion on Steam will also double as a sale. Meaning you’ll be able to secure full access to shooting down hordes of undead foes with friends (or adversaries) for only $23.99.

The first bout of DLC hit the co-op focused shooter last month, adding a survival gametype along with versus mode maps for two additional campaigns, namely Death Toll and Dead Air.

Read more: Left 4 Dead Now 50 Percent Off On Steam, Left 4 Dead Survival Pack Hits XBLM April 21, Left 4 Dead Survival Mode Details Hit, Left 4 Dead Survival Pack, Source SDK Hits This Spring, Crash Course With New Left 4 Dead DLC September 29 On Xbox 360, PC