Double Cross Rage 2 Mission
An ally: Doctor Kvasir
To unlock this mission, you first need to complete the Ground Control mission and reach level 5 of reputation with Dr. Kvasir. Soon after that, when you get in the car, Kvasir will contact you on the radio and this mission will start.
Thanks to the extra computing power coming out of Eco-15, Kvasir's work on the Cross-killing serum is close to completion. However, he is lacking one vital component - a string of the generals own DNA. Kvasir has an idea where to find it, but getting to it won't be easy... But hell, nothing ever is.
Related points of interest
Kvasir's Laboratory World Map
Lazarus Station World Map
To begin Double Cross you must first complete Ground Control.
Objectives of Double Cross
1. Talk to Kvasir
Kvasir will be waiting for you in his lab.
Possible bug and how to fix it: If you have a problem with starting a conversation, check this post and do one of the actions described in it. This should help. In my case (PC version), the first method worked.
If the talk prompt fails, go back up the elevator, to the other side of the bridge, then back again.
Thanks go to phantomfear949494 :-)
2. Reach the genetic research station
Go to Lazarus Station.
3. Find a string of Cross's DNA within the station
The Lazarus Station is a huge complex with many corridors, huge rooms and several elevators. Along the way, in addition to eliminating many enemies, you will have to free the prisoners ...
... kill the big cyber crusher ... (to kill him, shoot the blue element on his chest, when he kneels down, aim at the blue elements on his back, and when you destroy both, shoot at his exposed head)
... release another prisoner and talk to him ...
... and finally jump into the sling chamber and use it to get to the room where you will face General Cross.
4. Defeat General Cross
Avoid the general's attacks and shoot him until he hides behind a protective field.
When he hides under a protective shield, kill mutants and destroy capsules to which energy rays lead. When you do this, General Cross will once again be vulnerable. You will have to repeat this sequence twice. The second time the mutants will be stronger and there will be more capsules to destroy.
It's not over yet. The general will die, but his mind will be resurrected in a new body.
Luckily, you got a proper sample of his DNA.
5. Return to Kvasir
Leave the room with a door that opens and use the lifts to return to the surface. In front of the entrance you will meet some of the prisoners you saved.
Go back to Kvasir's Laboratory. Talk to Doctor Kvasir and then put the general's head into the extractor. After a while you will be able to take the serum.