Psyker
2.5-4% Bonus Critical Chance on Chained Hit. Stacks 5 times.
Up to 14-20% Strength, scaling with Peril.
4.5-6% Close Range damage on Repeated Hit. Stacks 5 times.
1-4 Burn Stack(s) on Critical Hit to a maximum of 3-12 Stack(s).
Made of glass, like most Psyker builds, but sprint-sliding forwards in between Accatran Mk XII Recon Lasgun bursts + Warp Speed + Disrupt Destiny movespeed buff + Mettle stacking quickly (Accatran Mk XII Recon Lasgun has crit chains, I believe) means you move STUPID fast when you want to. I got accused of hacking once while using this build and had to list all of those speed buffs. It's important to note that Dumdum will buff the damage dealt by Infernus burn stacks on targets within close range (12m? can't remember the exact number).
Outside of just moving quickly and using the Lasgun to pick off priority targets (and Disrupt Destiny targets), the build is still pretty well-rounded outside of being squishy. Covenant Mk VIII Blaze Force Greatsword handles crowds with light attack spam. Single target attack pattern is Push Attack into heavy attack spam. To utilize Unstable Power best (while outside of Scrier's Gaze), you can weave a few Assail throws in between your attack patterns. I've found this technique works better to keep your Peril high than it does to increase your Peril; I usually resort to this after using Scrier's Gaze so my Peril is already quite high.
There's probably an argument for removing Sprint Efficiency from a Curio or dumping Mobility instead of Collateral on the Lasgun, but I can't hear it over how fast I'm running.