Collectibles:
4 Artifacts
4 Logs
5 Weapon Parts
2 Blueprints
5 Upgrade Circuits

Mission Objective: Find Rosetta

There are 2 Boxes and an Upgrade Circuit (1/5) in front of the hut to the left of the ladder. Get this, then climb up the ladder.
As always Isaac gets seperated from the group and has to find his own way, this time the ladder breaks under his weight.

Mission Objective: Find a way into the facility

So run along the dark snowy path until you reach the fork. Take the right path first to find 2 Boxes and a good Scavenging Point. Return to the fork and continue straight on.
You will get to an old gate and see a dark figure run away in the even darker darkness. There is a door to the left, but it is locked, so continue towards the darkness where the dark figure ran to, to finally reach a door you can enter. Before entering the door drop another Scavenging Bot on the Scavenging Point a bit down the hill.

Inside the building are 2 Boxes and nothing more, the corpses can be stomped so this means no Headinfectors are close, so get outside again.
Danik's ship passes by over your head and you chat with Ellie about building a Codex before Danik does.

Mission Objective: Meet Ellie in the Rosetta Lab

Walk up to the sign and drop your Scavenging Bot on the Scavenging Point right in front of the sign. Now get the Seeker Rifle Blueprint (1/2) from the back of the snowmobiletruck and continue up the hill. You have to play the short circuit minigame before you are allowed to enter the next door.

After entering the Biology Sector you see the Heavy Standard Frame Weapon Part (1/5) and a Suit Kiosk right ahead. As soon as you start collecting the 2 wall cabinets around here you get attacked by some Head Infectors and 5 enhanced Wasters, this Biology Laboratory is filled with bilogical Anomalies now. When you get back into the round door room they will not attack that hard anymore, use this to your advantage as 5 enhanced Wasters at once are tough indeed.
When using the Suit Kiosk you can get the Legionary Suit that is probably better than your current suit. Also max out your RIG for whatever is not yet maxed out.
Then take the elevator up at the end of the hallway and enter the next door to get into the laboratory. Ellie and Carver are waiting for you, as is a small MedPack right when you enter.
After reading up on the topic Ellie wants you to put Rosetta together.

Mission Objective: Collect the Rosetta samples

So the first Rosetta sample can be found right in the room on the far wall where some computers are. Activate the switch on the wall so that the door in front of the Rosetta sample opens up, grab it with kinesis and drag it over to where you came from and where the slot came down from the ceiling. Stick it in and acknowlede by pressing the button.
That was easy, now on to find 4 more samples. Ellie even gives you a Reseach Facility Key to enter more rooms and laboratories.
Don't forget to nab the Upgrade Circuit on the far end of the room on a new game +.
So leave the lab and get down one floor via the elevator and enter the door past the Bench and the Suit Kiosk. There is some unhealthy growth all over the place. And there are explosive Cysts growing on top of the growth. Don't get too close to them as they spit out explosives. They can be killed with 2 shots and there are 5 of them in this hallway. You can get the Weedkiller trophy for not killing a cyst in this hallway. To do so, you need to stasis them and even catch the explosives the cysts on the ground spit out, as it kills them when it falls back on them.
At the end of the hallway are 3 Lockers guarded by the last Cyst. Then enter the door to the left of the lockers. Grab the Upgrade Circuit (2/5) from the wall cabinet and the Textlog (1/4). Then take the elevator down. Watch out while the elevator rides down, there are 3 Lurkers around, you can attack them while on the elevator already as they will do the same to you. And they continue attacking you when you are down and get out of the elevator, so kill them. Stasis one or two of them and concentrate on one and so on.

Then let your stasis refresh for a while and then open the fuse box and redirect the power so that is works. The power has to be balanced between the two options. In this case you just have to move the slot with the 50 on it to the right 2 times. That was hard, wasn't it. Nah, it wasn't. Like all of these so called riddles.

And as soon as the machine is running again 2 Wasters come in and attack you. I hope you have some stasis left as you have to fight them in a very narrow room. They are 1 normal and 1 enhanced Waster in case you want these indepth info. Get rid of them and ride back up and fight yet another normal Waster coming out of the vent.
Now it is time to get into the gas control room and kill all the cysts in the hallway by activating the gas. If you didn't shoot any of them before you earn the Weedkiller trophy now.
Walk along the hallway back to where you came from and take the first right into the door. Before entering the next door grab the MedPack and then enter the huge room behind the door.
There is an Audio log (2/4) right where you enter. Get the 3 Boxes and the Ammo Clip. After killing the Guardian attached to the wall at the end of the room grab the Alien Artifact (1/4) on the other side of it. Next to the remains of the Guardian is one more Rosetta Sample contained in a container. Push the button to open it and now you have to carry it to the other end of the room. As soon as you start dragging it you get attacked by 7 Wasters (3 normal, 4 enhanced), so drop the Rosetta sample as soon as you have to fight. Stay where you got the Rosetta Sample and kill off all the Wasters coming at you. Once they are all dead get the Rosetta sample to the entrance of the room and put it into the cabinet to send it to the lab to Ellie.
Before leaving drop another Scavenging Bot in here on the Scavenge Point.

Now get back onto the hallway and while we are here already, take the cargo lift up, we are going to the Paleontology next. Cross the short bridge over the hallway, enter the door, open the locker and get into the next door.
After you halfway crossed the long bridge 3 Slashers (2 normal and 1 enhanced) will appear right in front of you. Shoot your way through them and be fast as at the same time 3 more enhanced Slashers appear behind you. This is really tough and a lot of stasis comes in really handy here. If you are weakened or out of ammo (or close to) get back to the Bench and build some more ammo clips and MedPacks, you will need it soon.

After you crossed the bridge and entered the door grab the Ammo Clip, listen to the audio message playing, drop a scavenging bot on the Scavenging Point in here, use kinesis to open the box next to the only door onwards and use kinesis again to open the door. There are 2  Lockers on the other side of the door, also an Upgrade Circuit (3/5) and the Reaper Barracks Key. With the Reaper Baracks Key you can enter an optional Mission, named Scavenge the 163rd Reaper Barracks. I will remind you of this optional mission once you can actually start the mission as you can't do it right here, right now.
Also there is a Torque Room in here.




Is it worth it? You decide and then take the elevator down and get out smooth. There is a Feeder strolling around here. As soon as you attack the Feeder around 20 Feeders all in all will attack you. Use a lot of stasis, heal every now and then and go for the heads. This is really tough. Stay away from the vents as this is where they are coming from.
Then get the 3 Cabinets and take the cargo lift down. Listen to the Audio Log (3/4) and get ready for another strange puzzle.
You have to rotate the tubes in the middle of the room so that the Rosetta Sample can move out of it. There are kinesis handles on both ends but 3 rotating discs, so the middle disc is controlled by both handles. To get it done follow these instructions or play around yourself:

Turn left handle 5x
Turn right handle 5x

There are other combinations to align the discs correctly, but this one has the least side switching. If you already turned some discs before reading here this solution doesn't work anymore and you have to keep on turning until you solve it as there is no way to reset the positions.
Once all discs have the slot vertically get to the middle console and let the Rosetta Sample come out. Take it and put it into the tube to send it to Ellie.

After entering the door down by the tube with the discs you are at a fork. The door straight on finally brings you to the Optional Mission Scavenge the 163rd Reaper Barracks. Of course you need the Keycard to the Reaper Barracks to start the mission. If you feel like doing it now, do it. You should probably do it now.


So, back from the Reaper barracks? Fine, let's take the other door then. Kill the Cyst ahead on the ground and Danik will speak to you again. There is a Gas Control Station ahead (but dysfunctioning by now) and 1 box and 1 Upgrade Circuit (4/5) behind the station.
Get to the end of the hallway to use kinesis on the panel there and use kinesis again to turn the handle you exposed. Then run to the gas control station without getting too close to the gas and push the button inside here to close the door before the deadly gas comes too close.
Now you can use the Bench and enter the door in the hallway for 2 lockers and another door. Once you open the next door get in and stay on the move as 1 Slasher and around 16 Feeders attack you now. Use a lot of stasis and heal when you are low on health.
Once you are done with that and survived, drop a scavenging bot at the Scavenging Point at the right end of the room. Then get the 2 boxes (one it high up above the exit) and the Alien Artifact (2/4) close to the door. An Audiolog (4/4) can also be found here. And on a new game + you can even find an additional Upgrade Circuit under the Rosetta Sample.
Speaking of it, get the Rosetta Sample high up in the air to the right of the door and kinesis it to the slot where you can send it to the remaining people in your crew.
Now get up the small steps and exit through the door there. 1 enhanced Slasher and 2 pregnant Slashers are there. Deal with the enhaced Slashers first and shoot the pregnant Slasher only on the legs or it will spawn Head Infectors. Also one more Slasher and a Lurker will appear and also attack you.
Get the 2 Lockers and then get outside through the round door.

Danik is hovering above your head in his ship out here so you better run really fast up the hill and enter the door for safety. Get the 2 lockers and 1 box and be happy no head infectors got the 2 corpses. If you have a Scavenger Bot at hand you can backtrack a bit to the Scavenging Point outside where you were just attacked by the ship. The ship is gone but the scavenging point is still there. Then continue to the next outside part.

On your way back up the hill towards the main building you will encounter a new type of enemy. But first stop at the sign and drop a Scavenging Bot on the Scavenging Point there.



And now we meet our first Twitcher. And after the first one is gone 4 more Twitchers jump out of the snow on the way uphill and attack you really fast. Use a lot of stasis and aim for their limbs.

Back in the main building you can use the Bench and the Suit Kiosk for whatever you need them, grab the 2 cabinets that are refilled (also the Scavenging Point in the Biology is still/again active, get it if you want), then go to the last unused door between the bench and the elevator in the same room and use the keycard to open up the door.

We are headed for the Geology area now. Outside we find a box, some lose goodies and the Ripcore Weapon Part (3/5).
Now don't follow the questmarker over the bridge but go on straight instead. You see a Unitology Soldier commit sucide and can find 2 boxes and the Full Zoom Scope Weapon Part (4/5) out here. Also there is an unused Scavenging Point and 3 Slashers attacking you here.
Now get back to the bridge and head it down to enter an area with cargo containers all around. This is a good hiding spot for the 4 Stalkers here. Get close to the first row of crates and provoke them to appear and attack you, backtrack towards the bridge a bit and wait for them to attack and take them out. There are also 3 boxes and 1 Unitology Artifact (3/4) around the area. As you can't access the locked door yet take the cargo lift up.

At the upper end of the cargo lift are more cargo containers where even more Stalkers hide. 7 Stalkers after all and 3 Slashers are also there to make it hard for you. After you killed them all search around for 3 boxes (2 of them on top of stuff) and the S.C.A.F. Artifact (4/4). You can also find a new Scavenging Point up here.
Enter the Geology building. Use the Bench to create a Torque Bar if you have none at hand and do whatever you might need the Bench for. Get the Upgrade Circuit (5/5) from the wall cabinet and also grab the 1 Ammo Clip behind one of the containers.
Enter the next door and grab the goodies from the 2 wallcabinets. Also get the hard to miss Disposal Services Key that opens up an additional Mission, but we will get there later. As you know I will link you once you can get there within the course of this walkthrough.
Also there is another Torque Room right ahead.



Now get into the next door and get ready to play a little puzzely game, but not really a braintwister.
But before you do anything, stomp the 2 corpses here until they have no legs or arms anymore.
Then use kinesis to move the concrete block in front of the lasers to block them and move in the gap between laser one and two. Then switch sides and move the concrete block on and get to the next gap on the other side of the concrete block and so on. Notice the additional Upgrade Circuit on a new game + here. Then drop a Scavenger Bot on the Scavenging Point here and get the Rosetta sample and throw it to the beginning of the room so that you don't have to kinesis it all the way with you through the lasers.
As soon as you move towards the lasers on your way back 2 Head Infectors will come in, and if you stomped the corpses enough they find nothing to possess so they will come at you under the lasers and are an easy target, otherwise you have to deal with 2 possessed soldiers now. Then do the concrete block trick with the lasers again to get back and send off the last Rosetta Sample.

Mission Objective: Reassemble Rosetta

Time to get back to the lab where Ellie is. In the room where the bench is 3 Unitology Soldiers wait for you and want to be shot by you. On the field outside the geology section the goodies are reappearing, look where the Artifact was. Then take the elevator down and now you can enter the locked door and do the optional mission Disposal Services. I recommend doing it now as there is no better time. But do it only if you are strong enough as this is a real tough mission. There is also another goodie where the artefact was.

Back from the Trashdump? Got lots of good stuff? Almost died but still alive? Fine!
Let's head back towards the main lab building from this elevator at the crates now.
Walk along the bridge and get into the lab building, take the elevator up and meet Ellie.

If you want some more items, there are new lockers and reapperaing Items in the hallway to the left of the Bench in the main building, the Scavenging Points inside the biology section and far off on the outside have also reactivated.