Originally Posted by FireFlow PL
The Chronicles of Riddick: Escape from Butcher Bay Hint: The Missing Blueskin
If you already talked to the guy about killing all the Blueskins, forget it, it's too late you won't be able to complete this mission. This mission actually starts before you talk to him. After you kill Rust back in the single security level, on your way back to the courtyard, there is a Blueskin standing there. If you talk to him, he'll congratulate you on killing rust. When a guard isn't nearby, kill him.
The blue skin located in the Single Max section is not on the blueskin kill list, he dies in the cell block riot. The last blueskin needed to complete the mission is located in the upper mines. He gives you information about a keycard carrying guard you need to kill, but you do not need him to say it to do it. So you can just kill him right away or listen to his rambling. He attacks you after you kill the guard in the other room anyway.
I do not think that is accurate. I did not kill him after Rust. SPOILERS - I killed the one in tower 17, the one in the mines, then the 2 that come after you on your way back from the mines. I got the achievement for completing all side quests