Once per day, Nyctessa can cast Talking Corpse as an innate occult spell on an Immobilized or willing undead creature (DC 21), with a casting time of 1 minute. This provides more detailed answers than speaking with a non-undead corpse.
AC 19; Fort +10, Ref +13, Will +13
HP 60, void healing
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.
Speed 25 feet
Melee Nyctessa's Staff +11 (two hand d8), Damage 1d4 bludgeoning plus Sepulchral Drain
Effect Nyctessa expends the power stored in her staff. This turn she can cast one spell she prepared today and already cast, without spending a spell slot.
Sepulchral Drain
When the Nyctessa's staff deals damage to a living creature with a Strike, that creature gains a weakness 2 to void damage until the end of Nyctessa's next turn.
Effect: Sepulchral Drain
Taste Blood(void)
Requirements Nyctessa's last action was a fangs Strike that damaged the target
Effect Nyctessa drinks blood from the target, which must be a living humanoid, gaining 5 temporary Hit Points for 10 minutes. The target must succeed at a DC 21 Fortitude save or become Drained 1. Regardless of the outcome, the target is temporarily immune to Nyctessa's Taste Blood for 1 day.