Revolver Crit Veteran
Build for Darktide

Save your Infiltrate for repositioning or picking up downed players (high priority), as well as for safe scanner use. Tactical Awareness will help with keeping your Infiltrate cooldown as short as possible to have the ability in your pocket and ready for use. Toss Krak Grenades on heavy armoured targets or groups of Crushers that the revolver doesn't take down, with the increased rending you can 2 tap Crushers with headshot crits, and are easy to get guaranteed crits thanks to Surgical. For everything else go for headshots and crits as much as possible to 1-shot all elites and specials on Damnation except for Maulers (use a Krak grenade if you have you), Mutants, and Ragers. Be mindful of your positioning to get the most of the extra damage boosts from Killzone and Longshot.

I don't know what blessings are best for the shovel but I'm happy with mine. It works great for clearing hordes, the blessings help with knocking the mobs around so they can't hit you that much. I've run this with a chainsword with Bloodletter to one-hit Mutants with the special, and that attack also does great against monsters and bosses, but I find the horde clear is where the build falls short. 

Revolver is most important. You could probably use Crucian Roulette if you don't have Surgical, but taking one second to aim already gives you a 30% crit chance, and will easily give you 100% crits as long as you're patient. I find this more consistent than Crucian Roulette. I run this revolver setup on my Zealot and sometimes Psyker, and while it doesn't deal as much damage as on the Veteran, it is still a great option for taking out Specials and Elites before they get close.

Only thing the build really struggles with are Monsters and Mutants, and having to constantly reload your gun. It's not a spammy build by any means, and the better your aim, the better it will work for you. As long as you can keep killing specials or elites you will have continuous toughness regeneration (boosted by your Curio perks), and Iron Will will help for the odd hit that connects without nuking all your toughness. In addition, Survivalist granting +1 bullet per Special or Elite Kill, and if you are killing them with a single shot, well, you can do the math.

Blessings on the Curios can be whatever, but I like the extra health, as an extra incentive to not go down, and because your team's medkits will heal faster, restore toughness, and corruption from the current wound thanks to Field Improvisation. More health in each wound = more corruption healed. This node also grants grenades to your teammates when using ammo boxes, so more for them and even more Krak grenades for you! The Damage Resistance (Gunners) is also great because 60% resistance against the rank and file shooters means you won't instantly lose all your toughness when one gets a burst on you.

Focus Specials and Elites whenever they spawn to give your team some breathing room. You might not be able to solo carry, but it's strengths shine through keeping the more dangerous enemies under control throughout the map and in clutch moments when half your teammates are downed, or when a patrol of Crushers busts around the corner.