Descent to the Underworld

In search of Surgeon, Marked One enters X-17 laboratory.
Bring good solutions for close-range engagements as well as the means to take out a group of fast, hardy mutants.
==Walkthrough==
After entering and starting this quest, Hiko will message you. You'll need to find the radiation emitter and switch it off using a simple switch on it. Marked One answers that he will simply smash it into pieces, because the heat down the lab is not bearable.
=== Upper floor ===
As soon as you enter the lab, you will see 25 mercenaries on your radar, and two more will appear as you descend the steps. Your fire suit is terrible in a gunfight, and removing it will instantly kill you. The best tactic is to lure them into an ambush on the upper level, as you won't have to deal with open spaces and distracting vision effects from the emitter. A machinegun like an M60 or PKP "Pecheneg" will be extremely effective in holding the chokepoint safely.
After dealing with the mercenaries, follow the beeping noise and blow up the emitter with any explosive damage - even a single RGD-5 grenade will do the job. You're free to equip your regular armor at this point.
=== Lower floors ===
One floor below the merc hangout, Surgeon will be up on the observation deck of the embryo room. He won't be forthcoming with information and pulls out a dinky pistol shortly before being shot. Five Venoms will spawn after your conversation, so be prepared with massive single target damage or rupture resist and a crowbar. You can jump up into the observation deck window and onto the wire for a reprieve from the mutants.
Head back up one floor and look for a ladder into the vents. The container at the top will hold a map of Chernobyl-1 and a Colt "Anaconda".
=== Escaping the lab ===
On the surface, a large military detachment of 15 men (two with RPO-A launchers) will be waiting for you. Eliminate their squad leader and take his PDA, which contains coordinates for the two-way Darkscape - Chernobyl-1 transition. Afterwards, Hiko will contact you and arrange a meeting at Chernobyl-1.
Warning: as you pick the PDA up, a timer will be started. You only have a few hours to make your way to Chernobyl-1 through Darkscape. Don't postpone the next quest in the storyline, Meet Hiko in Chernobyl-1.
==Notes==
* It's better to sneak into the lab, as the military squad will fight with the natural Monolith spawn and give you more room to maneuver.
** Better yet, take the Monolith elimination cyclic in Jupiter from Demyan Ivanhoe and get the rewards for free.
* The mercenaries will drop additional Modified firefighting suits at varying condition levels. There appears to be no use for extra suits as of yet.
* Surgeon will not spawn until every single mercenary in the lab has been taken out.
* Likewise, the container with the map will not be populated until you talk to Surgeon.
* You can safely place a rucksack at the entrance to the lab and store loot there. This location is never used again and no NPCs will spawn here.
** A large amount of mutants will move in afterwards, but no elimination cyclics exist targeting them.
==Bugs==
* The mercenaries will clip through the walls and poke their guns through them to fire at you. Do not try to engage them normally.