Unnatural Enemy

or Gatekeeper Initiate feat, Region of origin Shadow Marches or Eldeen Reaches,

You receive a +2 bonus on Knowledge (dungeoneering) checks made in conjunction with aberrations. You also gain a +2 bonus on weapon damage rolls made against aberrations.

If you have selected aberrations as a favored enemy, the bonus on Knowledge (dungeoneering) checks instead equals your favored enemy bonus against aberrations. (The bonus on damage rolls is unaffected, but still stacks with the bonus from the favored enemy ability.)

You receive a +2 bonus on Knowledge (dungeoneering) checks made in conjunction with aberrations. You also gain a +2 bonus on weapon damage rolls made against aberrations.

If you have selected aberrations as a favored enemy, the bonus on Knowledge (dungeoneering) checks instead equals your favored enemy bonus against aberrations. (The bonus on damage rolls is unaffected, but still stacks with the bonus from the favored enemy ability.)

Aberrations are especially common in the Shadow Marches and the Eldeen Reaches. While only a few people actively follow the Gatekeeper traditions, many hunters learn to fight these terrors. You have been trained in the ways of aberrations, and you know how to recognize them and spot their weaknesses.