Kharostan

Greater Darkvision — A creature with greater darkvision can see perfectly well in areas of darkness and dim light, though such vision is in black and white only. A creature with greater darkvision can see through even forms of magical darkness.

Constant Spells — A constant spell affects the monster without the monster needing to cast it, and its duration is unlimited. If a constant spell gets counteracted, the monster can reactivate it by spending the normal spellcasting actions the spell requires.

Attack of Opportunity —

Necrotic Decay (divine, void) — When Kharostan dies, his daemon-tainted flesh quickly rots away and sublimates into a foul-smelling gas that fills a 10-foot emanation around his body.

All creatures within the area take 20d6 void damage as their flesh curdles and rots as well (DC 37 Fortitude save).

Void Healing — A creature with void healing draws health from void energy rather than vitality energy. It is damaged by vitality damage and is not healed by vitality healing effects. It does not take void damage, and it is healed by void effects that heal undead.

Devastating Strikes — Kharostan's melee Strikes ignore 10 points of a creature's resistance to physical damage.

Furious Sprint (rage) — Kharostan Strides up to five times his Speed in a straight line. He can increase the number of actions for this activity to 3 in order to Stride up to eight times his Speed in a straight line instead.

Rage (concentrate, emotion, mental) — Kharostan can't use concentrate actions except Seek and actions with the rage trait. The rage lasts for 1 minute, until there are no enemies Kharostan can perceive, or until Kharostan falls unconscious. Once the rage ends, Kharostan can't again for 1 minute.

Reckless Abandon (rage) —

Wicked Bite — If the jaws Strike was a critical hit, the creature takes both effects, rolling the saving throw once and using the result for both effects.

Drain Blood Kharostan drinks some of the victim's blood. On a failed save, the victim is Doomed 1 and Drained 1, and Kharostan regains 20 healing HP (on a critical failure, the creature is Doomed 2 and Drained 2, and Kharostan regains 40 healing HP).

Drain Vitality (necromancy) Kharostan draws out some of the creature's vital essence. The creature becomes Enfeebled 2 for 1 hour on a failed save (or Enfeebled 3 for 1 hour on a critical failure).