(Note about the enemies - You will encounter inmates in this level too, but these ones are different from Sanitarium. They have something like blades instead of hands which can harm you badly. Also, you need to spend more ammo in order to kill them. Spoiler: Where it is possible, avoid those mutants as much as you can, saving ammo for the two bosses Kurtis has to deal with.)

The brief cut scene shows you the area around.

Area with toxic pool - Head forward and open the gate at the end of the hallway. Follow the passage on the right hand side and approach the toxic pool. If you fall in there, you die instantly. To get past the pool, jump up to grab the wires on the right hand wall and start shimming left. Do not stop at all, because you have just enough strength to make it across. Pick up the Boran X Clip and return back. You can open the door to the office, but you need a code in order to use the pad on the Control Panel.

Open the gate next to the office and then open the door at the end of the hallway. There is a cell on your left but there is nothing interesting in there. The hallway exactly ahead leads you to a big blue metal door which you cannot open now. There is a cell next to it with nothing interesting in there, but if you enter you will alert two mutants. So, avoid this area entirely. From the door you just came in, head to the right and approach the second door on the left hand wall.

The cut scene shows the man using his farsee ability to view the room behind that door and the room behind the first door. Behind the first door, there is an inmate lying on the floor, having the code you need on its back.

Return back to the office opposite the toxic pool and enter the code to the keypad (17068). This unlocks the two doors you saw before. So, go back there. There is nothing in the first room with the dead inmate, so open the second door. As soon as you enter, a mutant appears in the hallway outside. Do not let it surprise you later, so exit and kill it. Pick up the Sanitarium Low Access Pass and the Boran X Clip from the dead guard, plus a Chocolate Bar from the desk.

Exit and go to the left around the corner. Use the card to the reader to open the blue metal door. The passage on the left hand side leads you back and by entering the cell you alert the two mutants you supposedly avoided before. Head forward and enter the cell to get a Boran X Clip from the bag on the cot. Return back, go down the ramp and open the door.

Square hallway - There is a guard ahead at the end of the hallway hiding in the duct. If your draw your weapon, you will aim at ahim, but if you start shooting, he will stand up. The metal door prevents you from killing him. Leave him alone and stay away from him. If you approach him, he will shoot at you. Three mutants are lurking around the corners and if you are fast, you can avoid them without losing health and ammo. There are also some doors around this area, but you cannot open them.

[Note - You can take a shortcut here (this works for both platforms). In order to finish the level, you are supposed to find a card (the Sanitarium Medium Access Pass), then use it to the socket at the far right of the area. You have one Sanitarium card (Low Access) and although you have used it once, you can use it again to the socket and skip the rest of the level. If you are interested in that, head forward and pass the duct with the guard. Follow the hallway around to the right and go to the end to use the card. Continue with the walkthrough below at Dealing with Proto.]

Morgue - As soon as you enter the square hallway, turn right and open the two glassed doors that lead to the morgue.

The cut scene shows Proto running out without hurting you. It then runs to the duct with the guard and kills him.

Area with chamber - Exit the morgue and go to the right. Crawl through the duct, where Proto killed the guard, and go down the stairs. Follow the hallway to the end. Open the metal door and exit to the circular walkway. Follow it around to the right and climb up the ladder. Turn left and cross the walkway to reach the chamber at the middle of the room. If you carefully watched the cut scene in Strahov Fortress level, you should have noticed by now that this is the area where Proto was first released, when Lara turned off the power.

Climb on the chamber and then jump to the bent walkway on the right. Follow it around, jump the gap and climb into the duct. Follow it to the end, by dropping down two ledges and then crawling through an opening. Drop down at the end and climb up the ladder to reach a small storage room. Pick up the Sanitarium Medium Access Pass from one of the dead bodies and the Chocolate Bar from the other corner. Push the button to open the door that leads you back to the square hallway. Go to the left and use the card to open the door. Go through it and down the stairs.

The cut scene shows the man entering the room below. He realizes that something wrong is going on, so he uses his telekinetic power to bring down a big metal door, locking Proto outside. But Proto finds another way to enter: through the duct above.

Dealing with Proto - You have to bring Proto down four times in order to kill him. This is quite difficult because he is moving\ jumping all the time and Kurtis is quite slow in order to follow his speed. There is a Boran X Clip on the right hand side of the room and a Large Health Pack on the left (when the cut scene ends). The Boran Clip is unlimited which means that every time you run out of ammo, a new one appears at the same place.

The best thing at this point is to have enough ammo in order to take Proto down for the first time. If you shoot at him and run out of ammo and Proto is not down, it means that you do not have enough ammo. In that case, start running around and try to get the Boran Clip. If you are lucky, you can pick it up. Otherwise, if Proto comes to you by the time you are about to collect the Clip, pressing Action to pick it up, Kurtis kicks\ punches Proto instead of getting the Clip.

If you are low on ammo - One Clip is enough to take Proto down once. So, every time you shoot Proto and take him down, run to the spot where the new Clip will appear, shooting in the air at the same time in order to empty your gun. If you do not empty your gun, the new Clip will not appear and the rest of the ammo you have is not enough to take him down.

Regarding your health, every time Proto bites you, you lose a small amount of health, as long as you step backwards whilst shooting at him. So, there is no reason to be nervous. Make sure you count the times you take him down (see the Bug note below). At the fourth time, Proto is finally dead. Approach him to trigger a cut scene.

The procedure (by Nicky) - As soon as you open the final door and go through it, draw your gun before going down the steps. This way, after the cut scene ends, you will still be holding it and gain precious seconds, as the Proto will be already at your feet and ready to attack.

Time to start the fight! Shoot Proto while stepping backwards, and when he gets too close, jump over him. Kurtis will turn around on his own to aim at him again, so keep shooting. In the unlikely case that Kurtis does not turn, make him roll or turn him around yourself. Tip by Lacek: more effective than jumping over it, however - and especially if you do not wish to lose any health, is side-jumping and diagonally jumping ahead (that is, if the Proto is attacking from the left, jump forward to the right and vice versa). If you manage to finish the first round without injuries, it is unlikely that you will run any such risk later.

After a while, you will see that Kurtis will not be aiming at Proto anymore. This is because Proto is about to leave and go hide up in the ducts. Proto will go up the tubes and disappear in the ducts, but in a few seconds, it will get back down to you. Before it does so, run to the metal doors opposite the switch (as shown in this screenshot) having your gun still drawn. Once Proto is on the ground, Kurtis will automatically aim at him. Shoot him a few times from the doors, and it will drop down senseless (1st time) most probably close to you. If he approaches much, jump over him.

Soon Proto will wake up. Before he does so, run close to the switch (if you have run out of ammo, go to the left of the switch and pick up the Clip). When he wakes up, Kurtis will automatically aim at him. Shoot him until it leaves to go hide up in the ducts again. Return back to the metal doors, so that you will be away from him when he returns. When he does, shoot again. Follow the above procedure until you bring him down four times.

For the desperate players - If you cannot beat Proto, take the advantage of a friendly bug here and freeze him (this works on both platforms). To freeze Proto, load a previous saved game before using the Access Pass that gets you into the arena. When the gate opens and you go through it, the game loads the next part. Save your game here before going down the stairs. Load this saved game and go down the stairs to enter the arena. After the cut scene that shows Proto bursting in, Kurtis will find himself next to Proto. This time though, Proto is freezed. You can run around Proto, kick him, punch him and do whatever you want, as long as you do not pause the game (Esc) or enter your inventory, because this will wake up Proto. Note, though, that this works only for the first round and Proto will wake up in order to jump to the ducts above, as he would do under a normal gameplay.

(Bug note - On both platforms, DO NOT try to save your game after taking Proto down for the fourth time. Go directly and trigger the cut scene. If you enter the inventory just before triggering the cut scene, Proto will not be on the floor after exiting the inventory. That way, you will not be able to trigger the cut scene and end the level, as the switch becomes accesible after the cut scene.)

When you finally bring Proto down for the fourth time, the cut scene shows Kurtis using his Periapt Shard and finishing Proto.

If you do not have enough ammo, empty your gun shooting in the air and collect the Boran Clip that will appear (to full load your gun). Use the switch close where the Boran Clip was to end the level.

The cut scene shows Kurtis returning back to the airlock where he had trapped Lara. Surprise!! She has climbed above, waiting for him. She disarms him and kills a mutant that was coming from behind him. Kurtis appreciates that and they introduce themselves (it was time!).

Kurtis says to Lara that Eckhardt plans to use all five Obscura Paintings to revive The Sleeper and rebreed the Nephilim race. In order to do that, he collects alchemically transmuted elements from his victim's bodies. He also tells her that Ekchardt is the original Black Alchemist and he is close to find the last Painting which is hidden in Lux Veritatis Vault beneath the Strahov. Kurtis asks Lara for the Periant Shard she picked up at the Louvre in order to destroy the Paintings. Lara "reminds" Kurtis that there are three Periant Shards and then he tells her that if all three Shards are united they can destroy Ekchardt permanently and that's why he (Ekchardt) keeps it safe.

Lara asks Kurtis about the Shards and he says that the Shards are ancient weapons of the Lux Veritatis and two of them were entrusted to his father. Ekhardt killed his father to stop them passing into Kurtis' hands, so he is looking for justice. They agree to work together: Kurtis will go after the third Shard and Lara will find the last Painting and destroy it.

In next cut scene, Eckhardt is talking with one of his men (Karel). He will let Lara find the last Painting for him and his preparations will be complete.