Punisher's "Exterminator Warrant' Stance
 Arbites Build - Warhammer 40k: Darktide 

A Build formed to maximize the effectiveness of the 'ad clear' shotgun variant of the Exterminator Shotgun, the Mk III. Terminus Warrant is grabbed for the sake of the Cleave on Ranged hits on top of the suppression, it's unfortunately the 'best option' for this even if the playstyle just doesn't work for me at all. I'd vastly prefer having a timer instead of stacks (like Weapon Specialist) as at least then it doesn't matter how many enemies are in front of me I know I have X amount of time/shots to deal with them. But nope, we got this crap, so might as well do our best to still make it work.

As it's a crit build, the only real option that doesn't make me feel like I'm missing out not taking stagger bonuses is the Tactical Axe. To be slightly different, I used the Mark VIII on this build, it's the III but strictly worse as it attacks slightly slower for no reason. But you still get the really high cleave push attack allowing you to use Rapid Movement to keep push attacking constantly, and you can even follow it up with a heavy attack if you want to send the back of the axe straight into the first pox walker in front of you and then immediately push attack again to correct your blunder. That's...something, at least it lets you keep Weight of the Lex active through out your combo more cleanly. Beyond that, just get as many ranged stacks as possible, swap to your shotgun and have however many glorious seconds it takes you to dump all 30 of your stacks against the wave and actually do something with your life, then sob as you run out and go back to the Combat Axe again. My kingdom for a Chain Axe...

But, while you have stacks the Shotgun does at least feel really good. You clean out and powder a vast amount of the wave every shot, it looks and feels quite nice, while being able to pop in a stun pellet if you need to 'hold it still' before wiping it away. It's fun stuff, to the point I take Ammo Belt so I can do it more/fire off none-empowered shots when desperately needed. Castigator stance is strictly there to allow for not needing Concussive + Suppression Protocol as whenever you get low just don't and you'll be fine, but you don't really need any of the upgrades as the base ability is busted on it's own. So I take extra cleave, extra ranged damage all the time, and dog. Because dog is good, especially for when one runs out of ammo (if they ever happen to). 

Just run around smacking everything you can with push attacks, getting to high ranged stacks as quick as you can, then dumping horizontal shots into the wave and watching it all go away. It's enjoyable, at least as enjoyable a Terminus Warrant build can be. If you are going for the penances, this is probably your best bet for getting them done relatively quickly, while feeling like you're still effective while doing so.