You can temporarily replace your soul with a fragment of the all-consuming void of Abaddon.
Prerequisite(s): Knowledge (planes) 9 ranks.
Benefit(s): As a move action, you can enter a state of emotional and spiritual hollowness. While in this state, you react to positive and negative energy as if you were undead— positive energy harms you, while negative energy heals you.
Whenever you are targeted by an effect that specifically affects living creatures or undead creatures, or that affects both in different ways, you have a 50% chance to count as an undead creature rather than a living creature. You are immune to effects that specifically target your soul (such as trap the soul). However, while under the effect of this feat, you cannot benefit from beneficial mind-affecting effects, morale bonuses, or bardic performances.
You can use this feat’s benefit for a number of minutes per day equal to your ranks in Knowledge (planes). These minutes need not be consecutive, but they must be spent in 1-minute increments.
Pathfinder Roleplaying Game Planar Adventures © 2018, Paizo Inc.; Authors: Robert Brookes, John Compton, Paris Crenshaw, Eleanor Ferron, Thurston Hillman, James Jacobs, Isabelle Lee, Lyz Liddell, Ron Lundeen, Joe Pasini, Lacy Pellazar, Jessica Price, Mark Seifter, F. Wesley Schneider, Todd Stewart, James L. Sutter, and Linda Zayas-Palmer.