Vaccine

Vaccine is the second mission in SAS: Zombie Assault 4 unlocked at level (?).

Plot
An infested planet that is about to be destroyed by orbital strike satellite contains a vaccine to the infestation which can be vital to human species. The player(s) much recover the vaccine from the lab and bring it to the dropship within 10 min.

Layout
It is the biggest map in SAS4, which is also a map where you much

proceed through and cannot go back.
 * 1) The starting area, which seems like an airport(maybe a starport).
 * 2) The second area, the train station.
 * 3) The third area, on-train.
 * 4) The fourth area, the train station where you'll exit to the outside
 * 5) The fifth area, the outside.

Loots

 * In the starting section, you can shoot open the door to a room in the top to collect a loot
 * There's a loot in the plane in the starting section
 * before you go into the train station, there's a loot in the righthand bottom rooms. One or the other.
 * In the train station, you can just leave alone the train for now and go to passageway to bottom to get to another train which is seriously infected. There's a loot all the way to right in the infested train.
 * Before you enter the labs(but inside the lab), you can go to top and break into a room to know which lab the vaccine is, and others are filled with zombies.
 * In the larger room between lab 1~3 and lab 4~6, you can break into a little room on top of it to get a loot.
 * In the top dropship possibility, you can find a loot behind a zombie spawning hole.
 * In the left dropship possibility, you can find a loot behind a zombie spawning hole.

Tactics
It is very important to have a good mobility. Assault class has the highest possibility of completing the mission because of its fast but effective melee attacks and its mobile assault team. If the player has bad mobility, it is not recommended to collect all the loots. Once the boss comes and the player it too weak to defeat the boss, the player can train the boss out of the small passageway and run to the dropship without having to kill the boss. It is recommended to ignore all the zombies if the player can since there's too many and it will take too much time. In multiplayer mode, only one person have to get on the dropship, so it's better if all 4 players get the vaccine and run in groups(sacrificing some of them) and get at least one player on the ship if there's very few seconds left.