GTFO: R6B1 - Hexahedrons (Main)

After beating R6A1, this level introduces fog mechanics - but thankfully its non-poisonous. Also while this facility seems pretty big and has multiple paths, there's actually only one path to go at any one time - so just lug around the Matter Wave Projector to the security door with the highest number you find and leave it there, even if you can't open it yet. Don't be afraid to just leave it behind too. Team loadout as before is:

DL: DMR/Sniper/Mines/Cudgel
Jim: Bullpup/HEL Gun/C-Foam/Hammer
Me: Pistol/Machinegun/Auto Sentry/Spear

You'll need a cell to open the next door so go West and defeat the Class IV alarm in your way. Mining the door and Jim going on c-foam duty to continuously ice while we did this makes it easy. Somewhere in here is the cell and also a SCOUT! Don't let those tentacles get you!

Quick scout recap: Snipe the head if its alone, or if you want to stealth kill it patiently wait around a corner for it to extend tentacles. When it retracts them, follow them back in while charging your melee strike and hit the scout in the head. Much easier with a spear now, but you still must abort your attack if the scout walks away OR if you start from the full extent of the tentacles (you simply can't walk up to him in time, hence you need a corner).

Most of the rest of the level follows suit. Explore, deal with sleepers, deal with scout, use mines and c-foam to beat class IV alarm doors, enjoy regular team scans, and especially enjoy the new checkpoint scans which soft saves your progress so if you die, you can start from that point. Just remember you don't need to visit EVERY room or kill EVERY thing. Stealth is actually an option if you are patient and have lock melters.

Checkpoint scans have a BUG: DO NOT be holding the Matter Wave Projector (or anything you didn't start the mission with) when standing in the scan or you'll be stuck holding it forever as I did if you need to reload.

Eventually you'll reach an awesome looking room where you need to plug the Matter Wave Projector in. Before doing so, deploy your remaining mines at around head height on the passage leading South back to the extraction point.

Once that's done, plug in the device, hike over to the terminal, type in the commands and quickly hide in one of the houses (lower one is better) before flying tentacle monsters come for you! Just save ammo and hide until you are teleported back to the facility.

Don't relax just yet, as you need to sprint back to the starting spot (or casually walk back if you bugged out like I did and were still carrying a matter projector) for the slow extract. The mines will help slow down these speedy pursuers. Also, learn from Rickon Stark and don't run in a straight line: they can't seem to hit you if you zig zag widely. Use the "drop box" as cover while holding them off (or take turns tanking) to eventually GTFO!