INFINITE STUN AND RANGED CLEAVE (HAVOC 40)
 Arbites Build - Warhammer 40k: Darktide 

Weave push attacks into your attack/dodge rotation (push attack > heavy > heavy > push attack) to build stacks of:

Justified Measures  Damage Increase on successful attack (Max 5 stacks / 10%)

Arbites Revelatum  Damage Increase on successful dodge (15%)

Suppression Protocols Damage Reduction on hitting 3 or more enemies (20%)

Hold the Line Damage Resistance for every enemy you stagger (Max 5 stacks / 15%)

Walk It Off  , Force of Will , Up Close Toughness Regen

and the most important ones for this build:

Drive them Back  Cleave Buff on push attacks (75% Cleave/5s)

Final Warning Ranged Damage Increase on staggering hits (15% Ranged Damage/5s)

Weight of the Lex Damage Increase on heavy melee attacks (15% Damage/5s)

Terminus Warrant Ranged Damage, Cleave, and Suppression on melee attacks (15% / 50% / 50% respectively) + Reload Speed

Essentially use your melee rotation to build the stacks, then pop Castigator's Stance  and start blasting into groups of elites & specialists to proc Writ of Execution .

AVOID USING THE SHOTGUN INTO GROUPS OF CARAPACE ENEMIES. Instead, use your shock mines to lock them down and beat them into submission >:)

Other notable interactions:

Try to keep 1 shell unloaded going into castigators stance, then reload and take advantage of Dispense Justice and Withering Fire .

Thanks to Ammo Belt you should be able to continuously fire into hordes of specials and elites without the need to continuously reload, due to Blessed Armament .

You can close large gaps and start point blanking enemies with the shotgun due to March while in castigators stance.

Finally, always aim for melee weakspot hits to proc Concussive and Soulguilt Scan .

3rd Blessing on Stamina Curio is optional, I like to switch between Health and Revive Speed.