"Within ten hours of the containment breach, nearly three quarters of the security and research detail at Horzine's London laboratory had been killed. Those who couldn't escape set up makeshift defenses in their dormitories, or the labs. In the depths of the facility, the incubators remain functional - spawning more and more clones. Your task is to eliminate every last one of the bastards."
Biotics Lab is a level set inside the labs deep within the Horzine headquarters. Its first incarnation, created by Alex Quick, was featured in the original Killing Floor mod and was remade for the retail version of Killing Floor by Tripwire Interactive. Players start in front of a destroyed elevator, their assumed entry point, and are faced with a T-junction in the corridor directly in front of them. Each direction eventually loops round on itself to the other passageways and there are no significant dead ends for the players to get trapped in, but that isn't to say it's not possible to get cornered or otherwise surrounded.
The corridors themselves are relatively compact, offering reasonable movement for evasion around small numbers of specimens. All rooms have weldable doors on the entrances as do some corridor intersections, which can make it easier to channel their numbers to the several defensive positions, or to block off your own escape if you are particularly unlucky. The majority of ammo and weapon drops are in corners, in alcoves, and hidden behind various scenery objects that can sometimes put you at a tactical disadvantage if sought during the waves and in the worst case scenario get you trapped by specimens. The chances of this happening, however, are fairly slim if you are observant enough of your surroundings.
The map is divided into three floors. The top floor, which is where the players start, is the largest of the three and contains the majority of the rooms, corridors, and item spawns. The middle floor, sometimes referred to as the second floor, is considerably smaller than the top floor, containing only four accessible rooms, three of which are interconnected in a 'U' shape off the corridor. The bottom floor is the smallest, with only one room that is accessible at all times.
There is a trader on each of the three floors.
- The top floor trader is found on a direct route from the spawn point, with no doors between the two points.
- The trader on the middle floor is inside one of the main defensive positions on the map – in the largest room of the floor, where partially dissected Clots are found.
- The trader on the lowest floor is one of only two rooms on that floor, directly across from a barricaded corridor; a spawn point for the specimens.
Biotics Lab, as it appeared in the original Killing Floor mod, was largely identical to its final form in the retail version. The main difference is improved graphics and additional traders; the original featured one trader found on the bottom floor. The top floor trader was originally the 'money room', which contained respawning riches and could only be accessed after unwelding the strong door at its entrance. The trader on the middle floor is a new addition for the retail version.
In the Killing Floor mod, the sections of the ventilation system in which Crawlers and Stalkers spawn were absent. Several ammo and weapon drops were also absent, and others were moved to accommodate the blockades. The various blockades in front of specimen spawn points were instead invisible walls that only blocked the player's movement.
- At the spawn, the vast majority of specimens will funnel through the middle corridor when the doors to the immediate left and right are welded.
- If any specimens that have less health than a Scrake attack the right door, then a grenade launcher can be used to easily kill them by firing through the portholes onto a nearby wall.
- Due to the amount of specimens that traverse the choke point, this is ideal for support specialists. One demo is advised to eliminate specimens on the right door, and Fleshpounds.
- Do not weld any doors in the middle corridor, as it may divert the specimens towards the other welded doors.
- Have at least one player positioned at the intersection so that specimens cannot spawn from behind.
- A major defensive position on the level can be found on the middle floor, inside the two large adjacent rooms. It is most effective when the door closest to the trader is welded shut, and it is ill-advised to stay near it because more specimens would be attracted to the door. The tactic taken from this point onwards depends on the number of people in the party:
- If there are only small numbers in the party, then it is advised to stand just outside the open door in the cross section of the corridors and use the room itself as a fall-back point.
- If the party is nearly full (4-6 players), then it may be too crowded to effectively employ the above tactic. In this situation, players can split up into two additional groups: one in the intersection with the three stairwells, and one down the other corridor in the room just at the top of the stairs. For the group stationed by the open door, only one good sharpshooter or demo player is needed to make sure that the other two groups are not attacked from behind and to cover their retreat when necessary.
- The corridor directly left of the spawn point, providing the door at one end is welded, can be used as a quick defensive set up for the first wave.
- In the first room on the left down the corridor, where several beds are found, players can barricade themselves by welding shut both of the doors. Incoming specimens can be shot from the inaccessible window. A second person, ideally a support specialist, can watch the door at the opposite side of the room. On solo, a pipe bomb or two can help defend instead.
- On the lowest floor, next to the trader, there is a small room with one door that can be welded. Caution must be given to the hole in the ceiling from which Crawlers and Stalkers can enter. There is nowhere to fall back to when overwhelmed, and once the glass window or door is destroyed, the specimens can swarm in.
- On the middle floor, below the two sets of stairs is a large hallway intersection with a weldable door on the right that leads to stairs down to the bottom floor where the trader is located.
- If said door is welded, a support specialist can guard the door as well as the two sets of stairs from Crawlers that spawn in the ceiling in the room above.
- The hallway behind is very long, making it ideal for a demo to shoot grenades at incoming Fleshpounds from either direction as well as for a sharpshooter, who can assist the support in guarding the stairs.
- A commando can set up at the other end of this long hallway and fire on specimens coming from the red-lit room.
- As teammates will be separated substantially in this defense point, communication is critical to signal when a heavier specimen is incoming so that firepower can be focused on it.
- The portholes on the double doors can be fired through; this can be used to your advantage when defending a specific door or a particular route from attack. Be careful when attempting to throw hand grenades them; if you miss the hole, then you can severely damage yourself and the door, and if the grenade lands too close to the door, then it may destroy the door. Grenades launched from the M79 or M32, however, cannot damage the door.
- Getting caught on the way back from, or to, the trader after downtime can be a hazard. There are many locations around the map that can be dangerous if caught alone in, but there is usually a second way to your chosen camping spot so you should not be afraid to run for it.
- When a door next to a large breakable window is welded, most of the specimens will ignore the glass and walk through the window, but some may focus on attacking the door.
The Trader following the April 12th update.