Primordial Caster
Requires Prerequisite
Prerequisite
The ability to cast at least one spell
Description
Upon gaining this feat, choose one of the following damage types: acid, cold, fire, lightning, or thunder.
Benefits
When you cast a spell that deals damage, your spell’s damage ignores damage resistance to the chosen type.
When you cast a spell that deals damage of the chosen type, you deal 1 additional damage for every damage die with a result of 1.
This feat can be selected multiple times, choosing a different damage type each time.
Source
Adventurer's Guide
a5e-ag_primordial-caster