VetPlasma
 Veteran Build - Warhammer 40k: Darktide 

Power Sword VI -  currently a very solid weapon with good horde clear, elite and boss damage (also finesse), but very low on defense and mobility. Tac Axe is a fun alternative. Cleave targets is the dump stat due to BM 

• Elite - The few enemies you can't one shot are normally in this category.
• Carapace- A key target for us are Crushers, and this allows us to nearly one shot head shot them with a push attack. Unyielding is a good option, as is Flak and Maniac for melee elites.

Blessings:

• Power cycler - The mandatory blessing on Power Sword to make it usable
• Brutal Momentum -  This PS mark does a lot of lights and push attacks, so Surge is not very effective. Slaughterer is a good alternative but you will suffer in clearing hordes and elite swarms. 

Plasma - The reason we are here, it will cleave just about anything even on uncharged shots. Carapace will still stop it, and that is it. No bosses do NOT stop your plasma shots, even uncharged. 
Headshot (charged or uncharged) will stagger mutants out of charges.
Perks: 

• Flak - This is necessary for uncharged one shot kills on gunners without crits.
• Maniac - oneshot body shots on flamers, and helps hit crit one shot on Mutants.

Blessings:

• Focused Cooling - Great synergy with Weapon Specialist as it will give you a guaranteed crit at 3 melee kills giving you a charged shot at almost no heat. Rising Heat is a great option, particularly if you don't go to the left side talent tree. Volatile also has high value as you should primarily be in melee, so your heat should normally be very low. 
• Gets Hot - regularly crit which will help reach quite a few one shot body shot breakpoints for elites and specials. 

While Rending Strikes doesn't help the Plasma gun much for anything but Carapace - it is fantastic for all our bleeding, and our melee weapon. greatly increasing our damage vs almost all priority targets.