Psyker Gun Magdump
 Psyker Build - Warhammer 40k: Darktide 

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With this build you can magdump clear waves with the Scrier's Gaze activated, try to wait for them getting closer so you can activate the Speedload and Dumdum blessings in order to basically delete entire waves of light/medium enemies (in close it works better if you don't aim so you waste less ammo on dead enemies). Try to use your ability as much as possible since it doesn't have a high cooldown and it makes you waste less ammo by making you deal more damage.

The Speedloader is kind of a core blessing for the build since you'll have to reload mid fight, A LOT. With the movement speed boost both from the Warp Speed modifier and the Mettle passive it should also be bretty hard to get caught off position while reloading or doing other stuff mid fight. With the Curious perks and blessings that i used it should also be pretty hard to die (remember tho that you're still a psyker and only have Toughness sustain).

I included the Brain Rupture blitz ability so you still have some range and you can deal with crushers or mawlers by using that from the distance, in combo with the Empowered Psyonic it makes it even easier to work out mid fight snipes to core enemies. You don't need it for medium enemies like ragers o flamers, just hold down mouse 1 while aming at the enemy to obliterate.

The build syncs really nicely with other builds that need crit or ability spam to work at their best since the aura boosts it and it reduces the ability cooldown.

Be aware that Scrier's Gaze stacks up Peril so be carefull with Brain Rupture and the melee weapon abilities

What not to do

The build struggles a bit against flak and carapace armoured enemies expectially with the ranged weapon (it means that usually you need half a mag to kill them) even tho the Kinetic Flayer helps quite a lot, you can always use the melee weapon for more armored enemies or if the wave gets too close and you can't reload the weapon.

This build can be VERY ammo hungry so try to not use it with other builds that require tons of ammo like the Plasma Gun Veteran build.

How can you modify the build

If you prefer you can use the Deimos Mk IV Blaze Force Sword but if a horde of enemies gets too close and you're out of ammo or can't reload in that moment you're basically dead, you can work around that with the other two blitz ablilities but you're giving up on all the extra range from Brain Rupture and the free damage from Kinetic Flayer, wich is really good expectially if it procs on a tanky enemy.