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Survival Map - Outpost 2

Defend the outpost while upgrading its defences. You get 1 upgrade point per minute you are alive, so spend them wisely.

Sand storm - Every now and again a temporary sandstorm will randomly be triggered that will obscure your team's vision.
Tunnel - After 10 miutes, the tunnels may open up and the infected will begin to use them to flank the outpost! To close the tunnels, you will need to enter them, find the keypad and press the numbers in order quickly (if you don't press them quick enough you will need to start over).

Base (B) - Better weapons will become available, walls will be replaced one time, teleporters cooldown reduced and finally 2 upgrade points are received per minute instead of 1.
Laser (L) - Activatable from the console on the wall, the laser will fry anything in front of the wall. As you upgrade it, it will do more damage.
Mines (M) - Mines with a cooldown become active infront of the wall. As you upgrade it, more will activate.
Slow (S) - A passive force pushes back infected in front of wall. As you upgrade it, it will be stronger. Very handy against smokers.
Protected Shield (P) - Activatable from the console on the wall, the wall will close preventing infected from entering the outpost. As you upgrade it, it will have a shorter cooldown.
Venders (V) - Activates the venders on either side of the wall, which spawn random items. As you upgrade it, you can use the vendors more often.
Health (H) - Passive effect inside the outpost which heals survivors, as long as they remain inside the outpost. As you upgrade it, it will heal more rapidly.