n medium aquatic humanoid merfolk 

Perception +8; low-light vision

Languages Aquan, Common

Skills Athletics +7 (+9 to Swim), Deception +6, Nature +8, Religion +8

Str +3 Dex +2 Con +1 Int +0 Wis +4 Cha +2

Items dagger

AC  17; Fort +7, Ref +6, Will +10

HP 30

Speed 5 feet, swim 30 feet

Melee [>] dagger +9 (agile, versatile s), Damage 1d4+3 piercing

Ranged [>] dagger +9 (agile, thrown 10 feet, versatile s), Damage 1d4+3 piercing

Primal Prepared Spells DC 18, attack +10; 1st charm, heal, hydraulic push; Cantrips (1st) dancing lights, detect magic, electric arc, ray of frost, stabilize

Hydraulic Asphyxiation [>] (divine, evocation, water) Requirements The target is fully submerged in water, within 30 feet of the merfolk wavecaller, and holding its breath. Effect The merfolk wavecaller commands the tides to crush their foe's throat, rooting the target in place and forcing it to choke up precious air. The target must succeed at a DC 18 Fortitude save or become immobilized for 1 round and immediately lose 1d4 actions' worth of air (or twice that on a critical failure).

Bestiary, page 235.