Valve has announced a new three-map campaign for cooperative zombie shooters Left 4 Dead and Left 4 Dead 2.
Valve has sent Eurogamer a teaser image for something to do with Left 4 Dead.
Check it out below. It was accompanied by a note that said: "In anticipation of an upcoming announcement from Valve."
The Apple-esque stamp in the top right, complete with "I hate different" tagline, suggests we may be seeing something Mac or iPhone-related.
Valve has finally patched Left 4 Dead 1 on PC to introduce competitive matchmaking for groups of four players.
Valve has announced that the Crash Course downloadable content for Left 4 Dead will be released for PC and Xbox 360 on 29th September.
Valve's Chet Faliszek has told Eurogamer that upcoming downloadable Left 4 Dead 1 expansion Crash Course costs money on Xbox Live because Microsoft insisted upon it.
Valve hasn't figured out yet whether the new Crash Course campaign will work with both Left 4 Dead and the upcoming Left 4 Dead 2.
Valve has announced plans to release a new campaign for the original Left 4 Dead next month, which will be free on PC and cost 560 Microsoft Points (£4.76 / €6.72) on Xbox Live.