Vigilant Headclicker - Shooter Removal
 Veteran Build - Warhammer 40k: Darktide 

Core Concept

Vigilant lets you kill shooters, gunners, and specials quickly and efficiently at any range. Click heads to build Marksman's Focus stacks and gain silly amounts of TDR with Exhilarating Takedown. At max MF stacks, you can even kill carapace enemies with chained headshots thanks to rending and crit bonuses. 

Opts for three toughness curios since you'll be clicking heads all the time, so you should have at least 2+stacks of Exhilarating Takedown for 60%+ of a mission. A stamina curio is worth considering on Deadshot builds though.

Talents

• I like taking the Fire Team aura if I can get away with it. Vigilant is very ammo efficient and can sustain itself just fine with vet's iconic passive, but defer to team needs.
• Reciprocity is disproportionately good on this build due to synergies with Deadly Accurate and the finesse bonuses from Marksman's Focus and Desperado . Vigilant crits also let you one-shot bodyshot shooters and most specials even if you can't always land headshots or need to hipfire in hectic situations.
• At least one rending talent should be taken to help the Vigilant kill reapers, plasma gunners etc, and to enable it to burst down crushers in panic situations. Take Rending Strikes instead of Chink in their Armour if your melee weapon has subpar ADMs against carapace (e.g. Shock Maul, Tac Axe).
• I consider Exploit Weakness to be this build's flex node, especially if you're running a Mk III Vigilant where you have more headroom on breakpoints. 
  • Trench Fighter Drill, Deadshot (particularly if running the Mk VII), Volley Adept, and Opening Salvo are my favorite alternatives
  • Duck and Dive and Tunnel Vision are good picks if you're running a melee weapon with a small stamina pool

Ranged Weapon

Every vigilant is solid, but I lean towards the Mk III. Always take +Flak as one of your perks.

Columnus Mk III Vigilant Autogun (three-shot burst)

• Highest hipfire spread of the three marks. Suggest ADSing most of the time, but can can freely hipfire when your crit chance is high or when fighting unyielding bosses.
• Headhunter can proc multiple times in multi-shot bursts - e.g if you land a single three round burst from the Mk III on a weakspot your crit chance for the next shot will jump from 10% to 70%. Leads to hilarious damage output against unyielding bosses since they have big weakspots.
• +Unyielding is my favored perk to capitalize on the above. Don't need kraks or +Unyielding on your melee weapon!
• Can kill reapers on H40 in one crit weakspot burst with ~13 MF stacks and max skirmisher stacks. Does not need Agile Engagement or Exploit Weakness active with +Unyielding perk.
• The only mark that can one-burst bodyshot kill scab bombers at H40 (needs max skirmisher stacks)
• The only mark that can crit one-burst bodyshot kill pox bombers at H40 (needs max skirmisher, does not need +Unarmored)

Graia Mk VII Vigilant Autogun (single-shot)

• Very accurate first shot from the hip, but subtle odd (horizontal?) recoil pattern on subsequent shots. Suggest quick-scoping after first shot if dealing with multiple targets in close proximity or you need sequential weakspots on the same target (e.g. a plasma gunner).
• Consider taking Deadshot, especially if you're already in the habit of quick-scoping  - best vigilant mark for the talent imo. Suggest replacing Headhunter with Surgical if taking Deadshot.
• Unlike the other two Vigilant marks, staggers shooters and gunners on bodyshots (however - like the others, does not stagger bombers)
• Can one-shot bodyshot H40 shooters, but needs the +Unarmored perk to kill dreg shooters without Agile Engagement active.
• Can two-shot reapers on H40 with favorable MF + Skirmisher stacks . With +Unyielding, doesn't need crits. Needs one crit without the perk (irrespective of Agile Engagement and/or Exploit weakness activation).
• Prefer taking +Unarmored for easy two-shot bodyshot kills on pox bombers and more reliable dreg kills. +Maniac and +Crit chance are my favored alternatives.

Agripinaa Mk IX Vigilant Autogun (two-shot burst) falls somewhere in the middle.

• Very controllable from the hip and the second shot makes the recoil less of an issue compared to Mk VII. Rarely needs to ADS to hit at least one weakspot.
• Two-shot bursts means Headhunter can proc up to two times
• With +Unyielding, can fairly reliably two-shot H40 reapers without crits. Without the perk, needs a crit
• Can kill reapers in one crit weakspot burst in very specific conditions (max MF stacks, max skirmisher stacks, Agile Engagement and Exploit Weakness both active, +Unyielding perk)
• Can one-burst bodyshot kill H40 scab shooters, and dreg shooters in with the +Unarmored perk.
• Probably the best of the three marks at killing Carapace
• Similar perk logic to Mk VII - Prefer taking +Unarmored. +Unyielding, +Maniac and +Crit Chance are my favored alternatives.

Melee Weapon and Blitz Suggestions

Melee weapon and blitz are flexible. Suggest taking something that can kill or severely debuff carapace (and contribute to killing twins, to boot). Some ideas below.

• Shock maul + krak synergy
  • Maul lets you apply Skullcrusher to improve the damage of krak grenades (and your team) against bosses - shout a (non-burgle) boss, hit with maul, apply kraks, profit. 
  • The maul's special action also does tons of damage to captain shields! 
  • Hammerblow provides safety and knockback even as hitmass starts to balloon on higher havoc, and lets you stagger crushers which means you can proc skullcrusher on them without having to use your special action.
  • Suggest swapping Chink in their Armour for Rending Strikes to help with Carapace
  • +Maniac is a must-take, killing muties and dreg ragers is painful without it. For second perk I oscillate between +Unarmored and +Carapace, but generally prefer unarmored to help compensate for lackluster cleave
• You can take a power sword if you want to be more optimal but a little squishier. 
  • Can swap the toughness curio out for a stamina curio
  • Consider taking  Duck and Dive for mobility and stamina regen, or upping damage output with Trench Fighter Drill