Veteran Grenadier (Combat Shotgun)
 Veteran Build - Warhammer 40k: Darktide 

Weapons

You can replace the melee weapon with your preference, since the Agripinaa Mk VII Combat Shotgun is a high mobility ranged weapon, you can use slower melee like the Munitorum Mk III Shock Maul, Achlys Mk VI Power Sword or the Cadia Mk IV Assault Chainsword. On the Falchion either use Wrath for easier horde clearing or Energy Leakage for more desperate brawls.

4x Shredder Frag Grenade with +25% damage and blast radius (5% chance to replenish on team Elite or Specialist kill)

You will hardly run out of grenades due to:

• Grenadier (+1 max capacity)
• Demolition Stockpile (replenishing 1 every 60s)
• Grenade Tinkerer (+25% damage and radius)
• Demolition Team (5% chance of replenishing 1 per Focus Target kill)

13/125 Shells in Combat Shotgun, first 2 shots +10% Crit chance, (+30% reload speed on Elite or Specialist kill)

Extra Shotgun Damage from:

• Ranged Damage Boost (+10% damage)
• Longshot (+10% to 25% damage)
• Opening Salvo (+10% ranged crit when full)
• Precision Strikes (+30% weakspot damage)
• Kill Zone (+15% base damage staying out of melee)
• Rending Strikes (+10% Rending)
• Superiority Complex (+15% base on Elites)
• Bring it Down! (+20% on Ogryn and Monstrosities)
• Focus Target! (+5 to +20% damage on target)

Tactics

Highlight Specialist and Elite enemies, ADS, kill, reload! Reload fully as often as you can! Shoot Scab Mauler in the groin!

Toss a Frag Grenade into the hordes, use your melee defensively until detonation, then clean up the rest!

Use Shredder Frag Grenade or your Shotgun Special (Slug) to stagger Bulwark and Crusher enemies!

Use your Infiltrate ability, to help downed team members, or get out of trouble and reposition!

Rely on dodging and cover to not get hit! You don't have a lot of durability with this build. Your extra health gives you a little more buffer to use Infiltrate and reposition.

Power the Aridin Mk I Power Falchion up for hard targets or if you have to clear a horde fast! Go for Weakspot Kills (heads) to activate Heatsink! Decapitator will synergize with that.

Talent options

You can go for Competitive Urge or Reciprocity / Duck and Dive instead of Toughness Boost if you are good at dodging.

You can go for Serrated Blade instead of Toughness Boost for better melee, mildly useful for horde clearing and finessing tougher enemies.

You can go for Survivalist instead of Fire Team, if the team is more ammo hungry than average.

Ability options

The Grenadier concept works with either of the 3 abilities, an argument could be made for any of them.

Infiltrate with Low Profile gives you the best survivability. Even after coming out of stealth, enemies will largely ignore you. You can remain in Stealth and block (to protect someone hacking a terminal).

Voice of Command  with Duty and Honour is good for support and boosting team survivability. Sadly if you get stuck in a horde with a bunch of ranged enemies all around you, while your team is down, you will not survive. But if the team is on their feet, around you, this is a good option.

Executioner's Stance  with Counter-Fire really helps picking out the gunners, but you become the most dependent on your team for survival. You really need them to have your back, if you get stuck you will likely go down and they have to pick you up.