I put dark matter on hold for the Double XP duration, I need the Dingo, Gorgon, 48 Dredge, P06 and the Drakon for Dark Matter. The pistols weren't that had to get diamond, play hardcore TDM, when I was doing them I deleted all of my classes and only ran the pistol I was working on, so that if I got mad I wouldn't switch to another class. If possible run quickdraw and high calibre, just run around the outsides of the map using either kinetic or vision pulse. The only issue I had was the Automatic Pistol, I struggled but because I limited myself to that pistol only I managed to do quicker than I expected. When you are doing the challenge for 5 kills runs Rejack, it will count as a bloodthirsty if you get 5 kills before you die after the Rejack.

Goodluck man