There is a new rescue mission assigned by the headquarter and they confirmed that the survivors are left behind in the building of Rex Research institute B-1. The journey is not that straightforward as the player will need to make a tour through block C before reaching their location.
Beware of the zombies attack and keep a look out at all times, as it can be hiding anywhere in the building. Clear all zombies in the area and save your comrades.
There are two safe areas in this map:
- Ducts: There is a long duct in this map which can be passable by two persons. There are two entrances to this duct.
- Engine room: There are high areas to be camped in this room. Note that there is a button for the light in this room.
- Turkey: This map was released alongside M134 Minigun, K3 and Zombie: The Mutation on 7 August 2013.
- CSN:Z: This map was released alongside Open Beta Test on 23 September 2014.
- Vietnam: This map was released alongside Open Beta Test 26 March 2015.
- There are two usable switches for lights.
- There is an unusable mounted machine gun in this map.
- Sometimes, you can get stuck when the door is closing.
- After the Free Update, the large machinaries now emit sounds.
- Abyss, the first map in the abyss series.