Arbites Execution Order Build (Havoc)
 Arbites Build - Warhammer 40k: Darktide 

Feel free to swap melee/ranged weapons. I recommend either the regular or Arbites Shock Maul for melee weapons, and think the Spearhead Boltgun is pretty good for helping fix the Arbites' boss damage issue. You can also use the Subductor Shotpistol and Riot Shield for a safety net in case you are caught in the open by gunners. All of these are mere suggestions though, and most weapons should work just fine for arbites (except the Shredder Autopistol and Vigilant/Braced Autogun. They aren't very good most of the time).

You can swap to either of the other abilities if you'd like, though I feel Break the Line is better than the other two by quite a bit.

Also feel free to swap to the Voltaic Shock Mine if you prefer it.

You may want to swap No Escape for The Emperor's Fist.

Both Strike Down and No Lenience are also considerations (+% rending talents). They would mostly help with damage against Crushers/Maulers, as rending doesn't have as much of an effect on Monstrosities (I think, I'm not actually sure about that).

Consider swapping some talent nodes for Shield Plates/Retaliatory Force if you want to use the Shock Maul and Suppression Shield or the Subductor Shotpistol and Riot Shield.

Rebreather is good. Not super important/required normally, but is almost required to even slightly enjoy missions with modifiers that cause more pox/tox gas.

True Grit is nice if you are worried about oneshots/massive chunk damage from things like Snipers, Poxbursters, Crusher/Mauler overheads etc.

Please see my other build 'Arbites Forceful Build (Havoc)' for a very similar idea, but with Forceful instead.