Favoured Enemy - Oathsworn Paladin

As a member of the Oathsworn, you have significant experience studying, tracking, hunting, and interrogating Duergar.

You have advantage on Wisdom (Survival) checks to track Duergar, as well as on Intelligence checks to recall information about them.

When you gain this feat, you also learn one language of your choice that is spoken by your favored enemies, should you be minded to.