Herexen

Creature 2

uncommon
Medium
undead
unholy

Perception: +8; darkvision
Languages: Common, Necril
Skills: Athletics +6, Deception +7, Religion +10, Stealth +6; Str +2, Dex +2, Con +1, Int +0, Wis +4, Cha +3
Items: dagger, defiled religious symbol of pharasma (wooden)

AC: 17; Fort +5, Ref +8, Will +10
HP: 30, void healing; Immunities death effects, disease, paralyzed, poison, unconscious, bleed

Final Blasphemy (divine, void) When the herexen is destroyed, it explodes in a wave of void energy with the effects of a 3-action Harm spell (DC 18 Fortitude).

The herexen is destroyed, so it doesn't gain any Hit Points from this use of harm, and it doesn't need to have any harm spells remaining to use this ability

Void Healing

Speed: 25 feet

Melee ◆ dagger +10 (agile, versatile s), Damage 1d6 + 4 piercing plus Heretic's Smite

Divine Prepared Spells DC 18, attack +10; 1st harm

Cleric Domain Spells DC 18, attack +10; 1st death's call

Heretic's Smite (divine) While wielding the favored weapon of its former deity (such as a dagger for an ex-Pharasmin herexen), the herexen's Strikes deal an additional 1d6 spirit damage to creatures with the holy trait.

Source: Pathfinder Monster Core

Running this fight? Add the herexen to the initiative tracker: type its name and the AC, hit points and Perception for initiative fill in, and the book button shows this stat block mid-fight.