Shield + Pocket Rocket
 Arbites Build - Warhammer 40k: Darktide 

Not the tankiest Arbites, but Forceful + the toughness regen talents at the top is enough to get through any Auric mission. This build is meant to be fun, survivable and consistent in Auric.

Priority Endowment gives +2 bolts in the magazine. A 10-shot Bolt Pistol feels great/is fun, and kind of makes up for not speccing into crit chance. 

Run 'n Gun is a contentious pick, but I just think it's fun. Let's you zoom around without having to constantly slide, makes the gameplay feel way smoother. The Bolt Pistol has great mobility, switching to it to quickly close the distance helps keeping you in melee. 

Reload speed is dump stat for Bolt Pistol, barely makes a difference. 80 Collateral lets you stagger Reapers in one shot. 

Arbites Grenade can be used to secure kills on Bursters, Trappers, Bombers, Snipers, Hounds, and with a few damage buffs going, Mutants and Reapers. Even before they get through doors. They stagger monstrosities. Helps to create space during hordes. 45 second regen time. Go mines if you prefer, but I think these are just tons of fun. Like exploding Zealot throwing knives.

All the damage, cleave and attack speed buffs lets you rip through armoured hordes. Maulers and Crushers are practically endlessly staggered.

Attacks in the Shock Maul and Shield's attack pattern where you use the shield has a ton of stagger. Use Heavy 1 to knock Ragers out of their attacks. 

Between the Arbites Grenade, Break the Line, the Shock Maul and Shields' flashbang special attack, and your high stagger melee and ranged weapon, you've got tons of ways of helping your team and controlling the horde. And the Bolt Pistol is a great anti-shooter and specialist ranged weapon, especially when Drive them Back and/or Targets Acquired grants it extra cleave.