Psyzerker
 Psyker Build - Warhammer 40k: Darktide 

This is a melee-focused Psyker, effective in Auric Maelstrom and below. Psyker + Berserker = Psyzerker

Initially I was trying to make it work with a force sword, since that would be cool, but unfortunately the low mobility on force swords makes them more trouble than they're worth on a build like this. Even with 80% Mobility stat, the dodge distance and movement speed are noticeably worse than the more agile weapons. My survivability instantly went up when I switched to the combat blade. You could also use a duelling sword, Devil's Claw sword, or pretty much any melee you want as long as it has good dodge/movement speed.

If you use something like the Devil's Claw that's weak against carapace, you probably want to bring a Zarona revolver or bolt pistol to kill crushers. Otherwise, the ranged weapon is mostly down to personal preference. You want something with decent crit scaling to benefit from Scier's Gaze and Disrupt Destiny, but use whatever feels good. I went with the infantry autogun since it's good for spraying down rager packs and stuff like that. Las pistol and recon lasgun are good options too.

You don't need a gun that's great at long range since you can pick off gunners and snipers with right-click Assails. It's good to toss out some left-click Assails periodically against trash mobs too, since you can get up to +20% weapon damage from Malefic Momentum.

For the aura, you can take either Seer's Presence or Prescience without changing anything else in the skill tree. Both are good. I chose Seer's Presence because high uptime on Scrier's Gaze improves both the offense and defense of the build significantly, plus cooldown reduction is universally useful to teammates whereas critical chance is only important to certain builds.

Since the build has 49% increased toughness from curios, it gets a lot of value from the +15 toughness nodes on the skill tree. With the current build, I have nearly 180 toughness. You can optionally drop one or two of those +15 nodes to get other things you want, such as Endurance or Surety of Arms. I prefer just having the higher base toughness in case I need to eat some ranged damage. Having your toughness broken is very dangerous on a build like this because it lacks the tools that Zealot and Veteran have to quickly recover from that situation.