Psyker
7.5-15% Weak Spot Damage. Weakspot Kills also ignore Enemy Hit Mass.
5-20% Critical Chance for 3s on Weak Spot Kill.
Up to 14-20% Damage on Hit (Staggered Enemy), scaling with Stagger.
14-20% Strength for 5s when every pellet in a shot hits the same enemy.
OOPS! All special shell spam!
In all seriousness, spamming headshots with the special ammo is a pretty good strategy if you can make those shots consistently but I personally throw an assail shard before every shot. Either the enemy is weak enough that assail takes care of them or it staggers them for an opening to shotgun them with improved damage from No Respite. Additionally, assail does a great job of clearing the chaff in mixed hordes (and doing more physical damage through Malefic Momentum ) opening up opportunities to take pot shots on elites. Either way, the most important node in the talent tree for this build to work is Surety of Arms, as it (+10% Reload Speed Perk) makes a noticeable difference in how quickly you can load the special ammo to pop off a shot.I also brought the machete, Turtolsky Mk VI Heavy Sword, to deal with hordes and one shot mutants with head shots / crits.