Due to a chemical imbalance in your brain, you are gripped by an inexplicable fear whenever you face a dangerous or frightening situation.
Drawback
After initiative is rolled but before you take your first action in combat, make a Will saving throw (DC 15 + 1 for each visible enemy). If you fail the Will save, you are shaken for the rest of the encounter, taking a –2 penalty on attack rolls, saving throws, and skill checks. If the save succeeds, you overcome your moment of fear and negate the ill effects.
Special
If you possess this mutation, you cannot become immune to fear. If you gain immunity to fear from any source (including being immune to mind-affecting effects), you instead only gain a +4 circumstance bonus against fear effects.