Yeah that would explain the misconception. BB is intended to be the tool that does all that, and back before the overhaul it largely did too. Anyway…
Once again, I apologize for my tone yesterday. I’ll try to deliver on what I said and give some tips now. However it cannot be overstated that there is just so much stuff to psykers that I couldn’t possibly sum it all up even if I had a full day to type this. So instead, I’ll just share a couple of beginner friendly (I hope) strong builds summarizing the basics on how to use them, followed by some details on why it works. Hopefully those details will help you understand the underlying mechanics so you can use them to make your own builds.
Darktide doesn’t have any one “best” build for any class, so please change stuff around as you like. There are countless builds and variations to each for just about anything in the game. Just be aware that there’s so much hidden info in the game that it’s easy to trade off a talent or a blessing that seems pointless, without realizing it was actually essential for the thing to work.
I’ll do the builds first, then some basic & advanced T5+ psyker gameplay tips in the end.
Crit Void
Build #1: Build Editor for Darktide - Create your own Darktide Builds - Darktide WH40k - Games Lantern
Variant #2 (talents only): Build Editor for Darktide - Create your own Darktide Builds - Darktide WH40k - Games Lantern
This is an all-rounder build that can deal with just about everything easily and from range. Aim for cleaving headshots, keep track of True Aim if you can (mods help a lot if you use them), keep the peril as high as you can for extra dmg & crit, use Vent on high peril to clear hordes.
Its biggest weaknesses is horizontal enemy presence since Void cleaves in straight narrow lines, and big groups of oggies & maulers too many to CC with Void alone (or if you can hear disablers or bursters behind them where Void can’t penetrate). For these you can use Smite to buy time and reposition, while again using Vent on high peril to clear and reduce peril to help with that.
Variant #2 focuses specifically on precision & crit dmg making it ridiculously strong. But it depends much more on those headshots, has a lower ult CD, requires more peril management, and ofc needs you to stack on Disrupt Destiny all the time.
Details:
(Note that Perilous Combustion and the Soulblaze stuff will be explained in the Purge build below)
- Warp Rider & Warp Nexus depend on high peril, try to get used to dancing around 80% or so, quelling between every 2-3 shots. High peril has other synergies too on many builds so it’s good to get used to it.
- Many talents depend on performance, the more specials you kill and the more crits you hit with, the more dmg, faster CD’s, more toughness regen etc you’ll have
- True Aim is amazing! It procs on headshot hits so a cleaving Void can cap it with a single good shot, letting you effectively get 100% crit as long as you do. Since crits trigger Surge, that’s 2 shots both of which can stack TA. On 5 stacks you know the next shot is a crit, which with Surge means you can put that shot exactly where you want it, so TA is one of the very few talents worth keeping a track of (mods help tremendously here, I recently got into modding and moved TA right next to my crosshair so I always know). Melee also stacks TA.
- Voids narrow attack makes it vulnerable melee from strays. Learn to dodge and put those between you and your real target and cleave both with one shot.
- Because of the Warp Siphon changes, burning an ult always dumps your Warp Charges taking away your dmg & peril efficiency bonuses. So don’t waste the ult on simple peril venting but make it count when you do.
- Venting Shriek (with Creeping Flames) applies its cap of 6 Soulblaze at 80%+ peril. 6 stacks kills all horde, with Warp Rider snipers too if you maintain ~50%+ peril after. So try to only use it at 80%+. It goes through map (walls, floors, everything) and has a huge AoE, making it a literal hall-sized anti-horde nuke on demand.
- Bc of the above, Vent is often best used in the direction of the biggest horde instead of just into whatever you’re currently nuking. Turn to face where it does the most dmg > blast the ult > turn back to whatever priority target you were focusing on.
- Note that Psykinetic’s Aura reduces your CD’s, and Warp Siphon stacks on specials, so sometimes it can be worth it to dump it early if you know you’re going to get tons of special+ kills and recharge the ult in seconds anyway
- Quietude procs on all peril reduction, passively or on using Vent. So if you’re in a pinch you can use it on high peril to generate toughness on top of everything else. As said earlier, staying on high peril has many perks.
- Primary fire is cheap, fast, and accurate. It’s great for finishing off wounded targets, quickly interrupting specialists or random melees, and also stacks TA.
Support Purge
Build: Build Editor for Darktide - Create your own Darktide Builds - Darktide WH40k - Games Lantern
I’m bringing this build up mainly to display some psyker curiosities it uses in the details. But it is definitely an extremely powerful support build. The idea is simple: burn everything and bubble up when your team needs it. Spam primary to prioritize CC (ragers & non-crusher oggies), secondary to prioritize damage. As long as you keep burning things and stacking up on Warp Charges and proccing Psykinetic’s Aura, the bubble will typically recharge long before the previous one even ran out. But the overlap is good, since a ton of ranged ofc breaks the bubble sooner. All in all this is a very safe and very team-friendly build that’s really hard to overwhelm.
It doesn’t have any big weaknesses, but it can get boring.
First I want to talk about just Purge & Soulblaze in general, because it’s a whole topic of its own and SB talents in general are imo poorly understood when they can add so much to any psyker build, not just Purge. Then after, I’ll sum up the remaining particulars of this build.
Details - Soulblaze:
- With both Purge and flamer, Burn and Cloud Radius are the priority stats
- Purge is 100% a crit staff: Crits apply 2 stacks of Soulblaze and do ~30% more stagger.
- SB has a logarithmic dmg curve. It exponentially increases the dmg of each stack doubling the dmg, slowly tapering down the higher the stacks go
- On Damnation 5 stacks barely wounds horde, 6 kills them & snipers, 8+ starts killing specials, 10-12+ elites etc. The more you go over the breakpoint stacks the faster they die too ofc. (for reference a similar build with Vent instead of the bubble can reach 21 stacks for over 400dps on monsters passively from SB alone, ~300+ without Vent)
- SB lasts 10s, then decays by 1 stack per second. Any new SB will stack and refresh the timer. It’s surprisingly strong against bosses, especially in long fights with lots of adds if you just stack it, do anything else for 10s, refresh, repeat. 1 minute of that can do about half the bosses hp in dmg passively.
- Purge SB stacks cap at 15, but the global cap is 31. While Purge can’t go over or refresh SB above 15, other sources like Vent or Perilous Combustion can and do refresh it.
- Wildfire is bugged and doesn’t work as advertised, but it still helps especially with In Fire Reborn
- Perilous Combustion means killing 2 specials+ near each other takes out the horde around them through SB, 3+ and now it’s specials too, 4-5 and now elites join the party. With Purge ofc this lets you reach SB breakpoints faster, or stack it past 15, making it crazy strong against all groups with specials+ around.
Details - Other:
- With Purge’s fire speed & crits Empathic Evasion makes you immune to ranged as long as you keep burning enemies. You can freely navigate the field and stare down 50 gunners, as long as you dodge or slide between the charges.
- In Fire Reborn (under Warp Siphon) works on anything that has your SB on it and is killed by you, they don’t have to die from the SB. With Purge it lets you reliably stack Warp Charges without depending on specials or the RNG of Psychic Vampire.
- Purge primary fire spam seems weak at first, but it can CC almost everything and 5s+ later they’ll die from SB
- Many think Purge is weak against Crushers. It’s not, just a bit slow to get there. Deimos with Uncanny Strike can deal with a few on its own, but with large groups you can stack SB on everything with Purge > use Deimos headshots or push attacks to stack Uncanny Strike and control the Crushers > switch back within 10s to refresh the SB real fast > back to Deimos before Uncanny runs out, and done. It does take 15-20s, but done right you can solo any number of Crushers with a few dodges in there.
- Bulwarks are easily staggered by primary without their shield. Circle around them or bait an attack, spam primary, and lock them in CC until they die.
- The bubble, or Sanctuary, is a fantastic ult. It blocks all ranged, snipers, trappers, flamers, and bombers and gives a huge passive toughness regen while lighting up dark zones (great for power outage mod) and seriously encourages even pubs to stick together where otherwise they would not. Use it accordingly.
- The recharge stimm is great on any non-Scrier’s psyker, but especially this one. Most of the time you can maintain the bubble indefinitely on your own, but not always. The stimm lets you bridge that rare gap when it really matters.
General Psyker Gameplay Tips
I’ve been adding to this around the day and really getting tired now, so I might cut this a bit shorter than intended. But I promise this stuff is useful.
Bare basics:
- Everyone, especially psykers on T5+ must master dodging, sliding, pushing, blocking and positioning
- Dodges avoid every attack but have a limit. They refresh in ~1-2s of not dodging, any attempt to dodge during this will reset the timer making you wait the full duration again. If you can’t dodge, use push or block until it resets.
- Sliding has no limit but only works against ranged. Dodge + sliding uses 2 dodges, but avoids everything and lets you move really long distances.
- Pushing uses stamina like blocking, but pushing 10 enemies is a lot cheaper than blocking them. Push also staggers & buys time, letting you instantly go back to offense or move away from the enemy.
- Blocking is important, but only use it when you have no other choice. It’s passive and doesn’t fix the problem, where dodging and sliding lets you attack at the same time, or just hitting with enough stagger lets you ignore defense entirely.
- Positioning is vital for psykers. Offensively it means lining up your shots for max dmg while staying out of sight or reach of the dangerous enemies. Defensively with the psyker’s low hp/toughness/dmg resist, getting surprised or caught without cover likely means going down instantly. All the time I see psykers go down on T5 because of a mistake they did 5-10s ago, letting themselves get surrounded or surprised with no cover.
A good practical example of the above is getting caught by surprise by ragers and horde just about to wail on your back. Block > turn around > push > dodge + slide backwards > switch to ranged & charge secondary during the slide > start blasting while picking distance, dodging or dodge + sliding again if needed. Do it right and you’ll easily focus them all down and come out without a scratch. But paying more attention or positioning better, you could’ve avoided the close call entirely.
Advanced tricks:
- You can slide while charging any staff or blitz, and fire during it. This is absolutely essential for T5+ psykers, since it lets you move at sprint speed while dodging ranged, charging and nuking at the same time. Sliding forward costs nothing, so you can do it as long as you like.
- Force Swords have super wide and deep pushes, and their push attack has a 9m range and always counts as a weakspot hit (proccing talents like True Aim and blessings like Uncanny Strike). Since Kinetic Deflection uses peril for blocking, you can use all your stamina for sprinting or pushing without worrying about defense. You can recover peril while pushing, and the Force Sword push can control all horde and most specials 360 degrees around you just spamming it forward and back, making it amazing for just buying time, moving through enemies, defending a decrypting teammate etc.
- The push attack can knock down anything aside from muties, even crushers with 2. It works while sliding or dodging, so it’s a fantastic tool for interrupting or knocking down specials, bursters, etc from range while moving around.
- Deimos comboes into 2:nd heavy from push or push attack. That 2:nd heavy is crazy strong and staggers or knocks down every non-boss enemy on headshots. So you can do things like walk up to a firing gunner while blocking it, push attack them down from <9m, charge heavy and dodge in their direction, and finish them off with 1 strike. Or push a mixed horde, pick out a special with the heavy while they’re staggered. Or push attack to stagger Crusher 1 > heavy to knockdown Crusher 2 > push attack 1 again to knock it down > heavy on 2 again and likely kill it, and now your rending is capped from Uncanny Strike IV. Etc.
- Quelling has a small DoT-like effect and can be done while sliding, making Mind in Motion useless as you can move faster while dodging ranged and still quell more than well enough. Even when I’m forced to pick that talent to get from Assail to a non-crit aura or Vent, I virtually never quell in a way that would get any use of it.
I have to stop now. But I hope you or others find this helpful. Sorry for the typos but I’m not going back to fix all that. 
Edit: One final addition. I only got into modding a few weeks ago, but if you’re at all considering it I must recommend it so much, especially for psykers. There’re many good mods but especially Custom HUD and Buff HUD Improvements. Moving the peril counter right to the bottom of the crosshair, and True Aim right next to it so I can keep track of both was huge. The peril wasn’t an issue before, but after the class overhaul and Scrier’s that really changed. (I experiment on everything all the time so almost every mission my peril works completely differently)