Stagger burn Psyker (havoc 25+ tested)
 Psyker Build - Warhammer 40k: Darktide 

this build focuses on maintaining stagger and bubble to allow the rest of the team to easily disperse enemies with ease, due to the brittleness applied via your staff. 

In turn with this, melee is a situational option, but the dueling sword offers a good balance between damage and movement, often being your preferred choice to poke at enemies that invade your space in the bubble, often a heavy followed by a special is enough to keep 99% of mobs staggered and away from you

while shield is up or viable cover is around, you can assist with special/elite elims by brain burst after placing your bubble, given your increased charge time for it and decreased peril gain after using your combat ability/. Seer's presence(your aura) helps reduce your CD for more bubbles which helps greatly under high ranged threats>

Your staff is used 95% of the time to constantly apply stagger with the hip shot(tapping) and deal with trash mob hoards with your charged.

crit hits count as you dodging, with one of your later nodes you don't gain a lot of peril, but have reduced toughness regen, counteracted by your curio. as you gain peril, your TDR increases, you can gain +3%(X5) damage for 10 seconds on crit hits

Soul blaze stacks for killing specials and elites, more CD reduction with your psy aura(different from seer's presence)

When you kill enemies with your warp attacks, you gain 7.5% toughness back, replenish 2.5% per 10%  peril gained deal up to +20% damage (scales with peril)

and your burn travels with wildfire as well( a switchable perk if you so choose, works well for hoards)