What changed in Left 4 Dead in 2011

Ability to recover achievement progress lost after The Sacrifice release.

In Versus mode, Tanks will spawn in stasis until a human player takes over, remaining invisible and invulnerable.

Survivor Bots no longer try to melee exploding barrels out of their way.

Survivor Bots no longer try to melee exploding barrels out of their way.

Players on the Infected team can now manually spawn during finales.

Ability to recover achievement progress lost after The Sacrifice release.

Tank speed is no longer reduced when on fire.

Bullets that first pass through an infected character before striking a Survivor are now ignored as friendly fire.

In Versus mode, car alarms will now trigger anytime a Special Infected pulls or stumbles a Survivor into an alarm car.

Added a vote option to toggle All-Talk.

Players on the Infected team can now manually spawn during finales.

Bullets that first pass through an infected character before striking a Survivor are now ignored as friendly fire.

In Versus mode, Tanks will spawn in stasis until a human player takes over, being invisible and invulnerable.

Special Infected that causes a Survivor to stumble into a 'ledge hang' situation will receive 50 points.

In Versus mode, car alarms will now trigger anytime a Special Infected pulls or stumbles a Survivor into an alarm car.

Tank speed is no longer reduced when on fire.

Special Infected that causes a Survivor to stumble into a 'ledge hang' situation will receive 50 points.

Added a vote option to toggle All-Talk.