L4D2 Witch
 Skitarii Build - Warhammer 40k: Darktide 

The Chordclaw Strike ability reminded me a lot of the Witch from L4D2, so I decided to make a build around (and found out that it was probably my favorite Skitarii ability). 

Main playstyle:

The main idea behind this build is that you are trying to have your ability available as much as possible, hence the choice of increased crit chance in both the weapons and skill tree (along with increased damage output, of course), to be used in conjunction with the Flux Conduit Build-Up modifier. As it is a mostly melee-focused build, the idea is that you are constantly at the head of the team. Because of this, I decided to choose the Integrated Refraction Emitter blitz over any sort of proper horde-control, as you will likely be targeted by both ranged and melee enemies a lot. Although horde control will not be your strongsuit, you can still deal with smaller hordes fairly effectively by using your Chordclaw's sweeping attack. The heavy attack on the Chordclaw is insanely powerful. A charged up heavy attack will one-shot a Crusher to the head (weakspot), even on Auric level missions. It is similarly effective against bosses. Whenever one of these tanky guys show up, it's your time to shine. You want to be in the thick of it, using your Chordclaw's sweeping attack on groups of less tanky specialists/elites, and using the heavy attack specifically on Ogryn-class enemies and bosses. If you run out of Refraction Emitter (blitz) charges, it's probably time to start playing it a little more safe (staying closer to your teammates, trying not to get surrounded/bodyblocked by enemies, etc.), until you find a blitz recharge lying around. Most importantly, make sure to wail at the top of your lungs as you charge toward your enemies and slice them to pieces.

Primary and secondary weapon choice:

After some experimenting, I found that I preferred having a more powerful, slower firing ranged weapon paired with a weaker but faster melee weapon. I ended up choosing the Branx Mk XI Phosphor Blast Pistol (my favorite Skitarii weapon ranged weapon) and Branx Mk XI Paired Transonic Blades. The Phosphor Pistol has good damage and piercing, along with being easy to handle and make snapshots with. The Transonic Blades have a fast attack speed and are somewhat good against groups of smaller/less tanky enemies when in their primary attack mode. Both weapons also have good blessings that give them extra crit chance, which works well with the rest of the build. Although other similar combos could certainly work just as well, if not better (The M35 Magnacore Mk II Plasma Gun/Branx Mk CV Galvanic Rifle and Branx Mk III Arc Maul/ Catachan Mk IV "Devil's Claw" Sword, etc, seem like good combos as well), I tend to like incorporating class-specific weapons into my builds.