I always wonder if that is why Karlach comes with 2 smite spells, one of fire damage and one of radiant damage? I have a personal theory/headcanon for that, but I never played EA so I don't know if maybe she just had it from the start because she was a paladin of sorts.
It's racials you get as you level up as a Zariel bloodline tiefling. Likely she's had so much contact with Zariel that that tiefling variation made the most sense for her on creation.
