Crash Course

Crash Course is the first DLC campaign for Left 4 Dead. It is free on the PC, but costs 560 Microsoft Points for the Xbox 360 version. It was released on September 29th. According to Valve, it is meant to bridge the gap between No Mercy and Death Toll.

Crash Course begins shortly after the events of No Mercy, with the Survivors starting out by the crashed remains of the helicopter that had rescued them. The helicopter pilot became Infected, and was killed by Zoey, causing the helicopter to crash into the ground. A whole selection of new audio has been recorded especially for this campaign, whilst still retaining the wit and patter that the game currently possesses. The density of the Survivors' dialogue is also noticeably higher.

The new campaign is much shorter than the others, which is a deliberate decision on the part of Valve. This was decided so that players could experience a much shorter, and much more intense game in Versus mode. Crash Course consists only of two chapters, which according to Valve, is a perfect length for a quicker, more decisive Versus match.

The two levels have been packed with everything players would find in a normal campaign. This can result in players finding tier 2 weapons almost straight away. However, the campaign will be faster-paced, and the Survivors could be attacked by the horde almost immediately from the very beginning. The levels have also been designed to give Special Infected plenty of advantages, once they learn the terrain.

Each of the two chapters (The Alleys and The Truck Depot) have their own major finale event as well, with the first one taking place on a blocked bridge. In order to clear the blockage of abandoned cars, the Survivors need to activate an artillery cannon to blow the vehicles out of the way. The Infected then swarm in on the area, which consists of a wide open space and a large house. The bridge itself is littered with cars and obstacles.

Fans of Left 4 Dead's safe room graffiti will be pleased to know that it returns in Crash Course.

The finale of Crash Course sees the Survivors reach a garage, where a bus is waiting at the top of a vehicle elevator, just out of reach. In what looks to be a homage to the Dawn of the Dead remake, the bus is armor-plated and is designed to take the Survivors through to safety and away from the Infected. Unfortunately, players must first get the bus down, and that requires use of a generator located in the parking lot outside.

The generator, unlike usual finales and Crescendo Event, takes time to activate, with players having to wait while the power charges up. Also unlike other finales, the generator sometimes fails, requiring a second activation. Once it's powered, the bus lowers and the horde arrives. This finale is particularly difficult for the Survivors because the Infected can attack from virtually every direction. After several long minutes of sustained horde attack, all of the power goes out.

Players are now stuck in the dark, surrounded by the Infected, and need to fight their way back to the generator in order to switch it on again, stuck in the open and having to slowly wait for the power to return. Of course, a Tank will make his appearance as with every finale. Once the bus is lowered, the Survivors enter in the back, and they escape.

Crash Course is intended to allow the full experience in Versus mode in just 30 minutes. The map will also include a recharge timer for the Infected and new item spawn behavior.

Trivia

 * This campaign includes quite a few new achievements, all specifically for it.
 * On the campaign poster, Louis and Francis are both dual wielding with a primary weapon and a pistol. However, this cannot be performed in actual gameplay.
 * Like in other Campaign posters, Bill and Louis are holding scoped MP5 submachine guns, which are not included in-game.
 * The body of the pilot can be found right behind you as soon as you start the first chapter.
 * The location of alarmed cars spawn differently every playthrough.
 * The Director has a tendency of spawning tier 2 weapons, pipe bombs, molotovs, and pain pills at multiple locations along the way.
 * Tanks and Witches spawn very frequently.
 * During the first chapter Francis and Zoey will talk about steam (a reference to Valve's Steam) if you pass the pipe leaking steam.
 * The rescue bus is fortified like the bus in the 2004 remake of Dawn of the Dead, including the cow-catcher's paint job.
 * In the safe-room, there is a map of the United States on the wall showing key regions "X"d out. The only two areas without an "X" are in Pennsylvania, where Left 4 Dead takes place, and New Orleans, where Left 4 Dead 2 takes place.
 * Francis taunts Zoey throughout the campaign for killing the pilot.
 * Bill has no new lines. When activating the generator he reuses "Watch my back" and "I'm getting too old for this horseshit." He says very little throughout the campaign, although he occasionally says "Get to the chopper!" when telling people to get on the bus.
 * Francis seems to be the most irritable and annoyed of the survivors, mocking the others, especially Zoey.
 * If a Survivor (except for Bill) walks over to the pilot against the wall, they will usually say something about him.
 * If the subtitles are on, one will notice that all Crash Course sensitive lines are Francis' dark gray color, regardless of who speaks.
 * Crash Course's finale is the only finale without someone to pilot the rescue vehicle, as it can clearly be seen that the driver's seat is empty. This is also the only finale with no radio to tell you to prepare (However, there is a corpse with an unusable hand held radio near the truck); this mechanic is replaced with one Survivor having to hold down the interaction button to activate the lift.
 * After the first Tank, the generator usually fails, requiring a second activation. This can happen from anywhere between fighting The Tank, to in the middle of fighting the horde. It also takes longer to restart it than the initial start.
 * When the van opens at the end of the finale, instead of the back sliding down, it breaks, even if nothing was hitting it.
 * The phrase "Cool story bro!" can be seen in the safe house. This is a sarcastic phrase used by Internet trolls in response to long, usually boring posts.
 * Crash Course is extremely glitched in some places. Players (both Survivors and Infected) can walk through the delivery vans, fences and the wall that you must blow down with the cannon. The glitch only seems to happen when people are in a Xbox Live game. There are also issues with some achievements glitching and not unlocking when playing an Xbox Live game: however, if playing single-player, local co-op, or system linked games, they appear to unlock just fine.
 * In survival, players can walk through the wall that must be blown down on The Alleys and "finish" the level.
 * Players can then start the timer for the next stage by shooting an alarmed car, though no Infected spawn.
 * If a player activates the generator, things will return to normal survival mode, until death, when the players are brought back to The Alleys.
 * During the finale, the Tank may randomly die without ever showing up, but his music cue can still be heard.
 * Crash Course is the first campaign in Left 4 Dead to occasionally have tier 2 spawn points featuring only one or two of the usual three weapons.
 * There is a glitch when searching for Crash Course in the campaign list. When browsing through the list of campaigns moving the selection arrow to the right, Crash Course is completely absent. However, when browsing through the campaigns moving to the left, Crash Course is the first to turn up.
 * During the finale when the rescue vehicle is being lowered, if you're standing underneath the lift you'll be incapacitated and then die a couple of seconds later.