Left 4 Dead 2 Projects
Cornered is a Survival/Scavenge map for Left 4 Dead 2. For survival mode the map is broken down into many smaller holdout positions rather than a single well fortified position. The layout and item pick-up positions promotes movement from one hold out position to the next in order to keep well stocked up on supplies.
The addition of the randomised lightning storm during play is to keep the map feeling fresh on multiple play throughs, the player may have tried all the hold out spots but the storm can change the game play of each dramatically as it lowers the players view distance and triggers many more zombie spawns than during normal play.