Merrow Peacekeeper (Berserk Supplement)
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Medium humanoid (Merrow), any alignment
Saving Throws Dex +5, Wis +3, Cha +5
Amphibious. The merrow can breathe both air and water.
Fin. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage.
Merrow's Song (Recharge 4-6). Any creatures of the merrow's choice within a 20 ft. cone centered on the merrow must attempt a DC 13 Dexterity saving throw. On a failure, they take 5 (2d4) thunder damage and 5 (2d4) psychic damage, and are stunned until the end of your next turn.
Leadership (Recharges after a Short or Long Rest). For 1 minute, the merrow can utter a special command or warning whenever a nonhostile creature that it can see within 30 feet of it makes an attack roll or a saving throw. The creature can add a d4 to its roll provided it can hear and understand the merrow. A creature can benefit from only one Leadership die at a time. This effect ends if the merrow is incapacitated.
Merrow peacekeepers are largely non-combatant, though they have the power to do battle if necessarily, particularly against the odd kelpie that takes residence on the various islands many commoners laze on. In larger merrow societies, peacekeepers act as large-scale anglers, and construct their various aquatic buildings with nothing but their voice and raw stone.