Peter König is a concept art legend. Over the past quarter of a century his creature designs, sculptures and animation work have been featured in blockbuster hits like Jurassic Park, Starship Troopers and Cloverfield.
Which is all well and good, but he's also spent the last four years working as a concept artist, modeller and texture artist at Valve, where he's lent his talents to the Left 4 Dead series, Portal 2 and DOTA 2.
While there sadly aren't any images from Portal, and only one from DOTA 2, König's Left 4 Dead stuff is a treasure trove of the walking dead, rotting flesh and rejected designs for special infected that involved shooting rats out of a zombie's stomach.
You can see a nice collection of König's body of work, both in games and cinema, at his personal site.