Product Update - Valve
Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

General:
- Added game event calls for onslaughts to explain to players that they need to fight their way to the safe room.
Modders can make use of this by pointing an info_game_event_proxy entity to “explain_onslaught”
- All maps received minor tweaks and bug fixes , the significant changes are listed.

Crash Course 1 – The Alleys:
- Item spawn density revision.
- Opened the side-doors leading to potential item spawns.
- Switched out L4D2 mounted gun for the L4D1 minigun.
- Removed exploit where survivors could get onto a roof near the drop down to the river.

Crash Course 2 – The Truck Depot Finale:
- Item spawn density revision.
- Switched out L4D2 mounted gun for the L4D1 minigun.
- Removed exploit where survivors could jump onto the top of a generator during the finale.

Cold Stream 1 – Alpine Creek:
- Fixed water moving uphill in some spots.

Cold Stream 2 – South Pine Stream:
- Removed “shortcut” through the bushes between a pair of barricades leading to the barrel explosion event.
- Added tooltip to prompt players to fight to the safe room when the onslaught begins.
- Tuned the horde numbers back a bit during the onslaught event.
- Moved the sun to help guide new players.
- Blocked ability to get under the river.

Cold Stream 3 – Memorial Bridge:
- Added many more infected ladders around buses.
- Rebuilt catwalk under the bridge to prevent players getting caught on geometry.
- Moved the M60 and Laser Sights upgrade to more vulnerable locations.
- Removed ammo pile in the shop just before the junk yard, but kept the weapons.

Cold Stream 4 – Cut-throat Creek:
- Added some light cover for the tank in the basin area.
- Removed survivor manhole exit into the second half of the map.
- Added side-hall in the sewer as a shortcut for infected players going to the second half of the map, and as a strategic place to spawn in the sewer.
- Added new truck depot area near the tower for infected to spawn in.
- Opened a warehouse door for infected to spawn in.
- Added infected ladders in the CEDA checkpoint area.
- Rebuilt stairway up the finale tower to prevent players getting caught on geometry.