Nixie
About
The singing comes up through the water, which is why it sounds the way it does - close, warm, and slightly wrong, like a voice heard through a wall. Nixies sing only where the water is deep enough to be worth the trouble. Millponds, river bends, the black stretch under a bridge. Shallow water gets nothing from them at all, and the villages that know this build their fords wide and keep the children off the banks.
Stats
Save Rolls
Traits
Special Attack
The Song Below: 60 ft, and only from water at least a fathom deep. Save Wis Mind, fail save roll 1d6+1 psychic and the target moves to the water's edge and then into it, cooldown 2 rounds. Pull Down: bludgeoning, melee 5 ft, +2 to hit, 1d6+1, with Advantage against a creature already in the water.
Special Defense
Needs the Deep: it cannot sing, and will not fight, in water it cannot submerge in. Driven into the shallows it simply leaves. Bargainer: nixies keep bargains exactly and will trade a safe crossing, a drowned body or a lost thing from the riverbed for something they want, and what they want is rarely coin.