Pandion Knights

A sequel to Valve's cooperative zombie shooter Left 4 Dead was just announced at Microsoft's E3 Media Briefing, slated to arrive November 17 on PC and Xbox 360. 

New survivors in new locations--the trailer teases Louisiana--gain melee combat with weapons such as a chainsaw, frying pan, axe and baseball bat to fend off new zombies.

Valve promises "a much larger game than the original with more co-operative campaigns, more Versus campaigns, and maps for Survival mode available at launch." The gameplay-controlling AI Director is also ramped up, now able to change weather effects, world objects and pathways to keep players on the edge of their seat.