Edgelord Walking Nuke Overload Psyker
 Psyker Build - Warhammer 40k: Darktide 

THIS IS AN OVERLOAD BUILD- YOU WILL KILL YOURSELF OFTEN IF YOU DON'T MANAGE YOUR PERIL PROPERLY
So, this isn't the most efficient or the most powerful psyker build, but it's certainly fun. 
Almost all of your damage is going to come from peril generation.
Blocking, sword activation, staff primary, staff secondary, charging the staff's secondary, and taking melee damage all generate peril. 
As peril generates, your melee damage increases, as well as weak-spot damage, critical damage, and critical rate. 
Use Crystalline Will to take out specialists and elites, but if there aren't any around you will take corruption on overload- this is when you use Scrier's Gaze to rapidly quell peril in the middle of combat without having to stop and manually quell.
Dodge OFTEN, carry either a Medicae or Concentration stim. 

note- you dont need to USE the staff to generate peril, charging the secondary will charge peril at a slower rate, allowing for preparation before combat. 

note 2- you can switch soul blaze instead of smite, and take the blaze staff instead of electro, but the build will be less efficient at dealing with crowds/hordes. (you use the stun from the electricity to stop crowds in place and then use the activation from the greatsword to cut through them all at the same time) 

all in all, it's not great for Auric, though with a good team you should do just fine.
NOT  havoc rated build, and the build itself is NOT in stone. 
Tamper with it, experiment and see what works. 
This build was for FUN not meta.