DarthSidious
 Psyker Build - Warhammer 40k: Darktide 

this build abuses toughness Regen mechanics from coherency, for this we want a low toughness value (unfortunately we are forces to pick up 2 +25 toughness nodes which make this build worse)
coherency toughness Regen only works when you are not being targeted for a melee attack, however smite is one of the best stun effects in the game. allowing you to Regen toughness mid combat. at a fast rate even with empiric resolves de buff
stack soul blaze with your inferno staff, switch to smite, melt the hoard, stun everything, spam bubbles

the mk4 force sword is set up for max damage against crushers, bosses, large targets etc, attack pattern is light light heavy for jabs only or heavy light heavy to start with an overhead attack
if you prefer to do only overhead attacks switch to the Mk2 force sword and use the heavy heavy heavy attack pattern

you should focus on clearing the hoard and stunning as much as possible, protecting your team from snipers, trappers, gunners etc using your bubble, allowing them to be as effective as they possibly can

the one downside to this build is that. you can't really solo carry. so you need to rely on your team mates actually being good at the game

if you want to trade perks / dont want to instantly kill crushers with your sword. the ones i would conciser dropping first are 
Perilous Combustion (since you can still stack soul blaze with staff)
Vulnerable Minds/ Warp Rider (although you will be loosing damage for sword/smite)
Puppet Master (this is important for coherency Regen reasons when team members are spread out)
Charged Strike (this is important for sword)

perks you may want to add are

Psychic Leaching

Mind In Motion
Immaterial Focus

Penetration of the soul

perks i would never remove are

Empyric Resolve 

Solidarity

Charged Up

Sanctuary

Enfeeble