Artificer
Craft Turret doubles the action economy. The S-tier pick.
Signature skills
Playstyle
Drop a Turret on turn 1, then use your own turns for high-scaling abilities. The Turret handles scaling pressure; the caster handles priority targets.
Strategy
Maintain INT as primary stat so the Turret picks the highest non-INT secondary (DEX → Snipe is the typical optimized path).