The Last Stand

The Last Stand is the name given to the "fifth campaign", and is the final campaign in Left 4 Dead, and is only for Survival Mode. It has only one map called The Lighthouse. Consisting of basically a neverending horde, players must survive for as long as possible. It is possible that Valve is going to release more maps for this campaign for use in Survival Mode. It should be noted that the tagline is "It Doesn't End Well", as Survival Mode always ends in the Survivors being killed.

Strategy

 * A good place to fight the horde is from the top of the lighthouse on the wraparound walk way. This gives the best line of sight and forces all of the Infected to climb up, slowing them down greatly.
 * Having at least one Survivor with a hunting rifle is almost necessary given the sight lines available and the constant threat of distant Smokers pulling Survivors off the roof.
 * Assault rifles also come in handy to shoot the Infected and Tanks before they even reach the Survivors.
 * Shotguns are extremely useful when Hunters pounce and for clearing out any Infected that do make it up to the Survivors. However, fighting Tanks from here is a bad idea, as explained later, so using a shotgun against a Tank here is ill-advised. Therefore, having no one with a shotgun is not a bad idea, while having more than one Survivor carrying a shotgun is a waste.
 * Molotovs and pipe bombs often start up here. If an ammo run is needed, the best place to run is the roof of the generator room since it requires less climbing and keeps you off the ground.
 * Investing time before the round starts to bring all of the gas cans and propane tanks up to the very top of the lighthouse is a good idea. The best place to keep them is on the highest part of the lighthouse, above the wraparound balcony, to prevent stray bullets from causing the team's death. A sniper perched up here can throw them down and use them when/where needed. However, camping up here makes an easy target for Smokers, so the sniper has to keep moving and be alert.
 * The downfalls to this strategy are the breakable railings and possibility of getting knocked off the roof and killed by the Tank. To avoid these pitfalls, keep moving so Smokers can't drag anyone off the roof and take care to stay away from the edges, where someone might be left helplessly hanging. Also, when Tanks come, it's much wiser to move down to a lower level of the roof as the blind corners and deadly drops give Tanks the only advantages they need.
 * Smokers generally attack from behind trees on the hills located to the Survivors left from the start as well as from the ground and lower levels of the roof on the waterfront side of the house. On the hill side, Smokers are extremely difficult to see or shoot, and on the water side they can pull the Survivors all the way down to the ground, causing almost certain death for the victim. The damage doesn't come from the fall but from being pulled so far away from the rest of the Survivors.
 * The best way to fight Smokers is to keep moving, watch for the Smoker's spore cloud, and carry ranged weapons. Good communication with other players is also critical to staying alive.
 * A fun but wasteful idea is to spread all of the gas cans and propane tanks out on the ground around the light house. When the horde comes, throw a molotov cocktail or pipe bomb down and watch the entire ground be set on fire with intermittent explosions. As before, this is fun to watch but leaves the Survivors with no gas cans or propane tanks to fight with.
 * Another good spot to defend from the horde is inside the house, all of the Survivors should use auto shotguns or three auto shotguns and one assault rifle.
 * The advantage to this tactic is that the Hunters and especially Smokers become way less effective. This is because each Survivor is positioned in their own corner of the room. When a Hunter pounces someone you just shoot at it once and it should be quickly killed. When a Smoker tries to drag you out they are basically standing unprotected, which means that you can shoot them directly or go ahead and punch your friend free.
 * The gas cans should be stationed around the house and especially outside the front door to keep that way clear. You should also keep yourselves stacked with pipe bombs.
 * The Tanks die really quickly if you are using shotguns at close range and this strategy deals with the Tank at very close range. When a Tank arrives, have everyone in the group concentrate their attacks onto the Tank and it should be dead in seconds.
 * Do your best to avoid incapacitation as it can be quite hard for the others to get you up. You may wish to heal slightly earlier than usual.
 * There is a glitch in this level that leaves you untouchable by all opponents, save for the Smokers. To exploit the glitch, one must go down the hill until they find two trees sprouting in front of a rock. By jumping between the trees and the rock, your character becomes stuck in the space, and Infected are usually unable to reach you. Tanks also seem to die upon approaching. Even when grabbed by a Smoker, your character cannot be dragged, and therefore will not die.

Trivia

 * The Survivors on this poster look almost exactly the same as they do on the Death Toll poster, aside from a different background and mirror.
 * Unlike every other poster, Zoey's hair isn't in a ponytail.
 * This is the only campaign that will end in the death of the Survivors.
 * This campaign also currently contains no safe rooms. The only safe time is the period before activating the generator, thus alerting the horde.
 * The Last Stand is the name of a popular zombie flash game where a survivor and people that he collects along the way try to keep off hordes of zombies from their base, similar to how the Survivors in this campaign must keep off the hordes. This could be a reference to the game.
 * Although there is no definitive storyline involving the five campaigns in Left 4 Dead, the campaigns can be linked to one another with careful observations but this does not define it as Left 4 Dead canon.
 * There is a possibility that this campaign would come after Death Toll, for in the water one can see a sinking vessel, it appears to be the same boat that rescued the survivors in end of Death Toll.
 * If you throw a Molotov at the inactive bulb in the lighthouse, the bulb will switch back online.
 * The light, if seen from a distance, appears to be lit, but upon closer inspection, it is not.
 * Writer Chet said this campaign explains what would happen if the Survivors took a wrong turn.