Neptune's Harlot (5e Creature)
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Large beast, unaligned
False Appearance. While the neptune’s harlot remains motionless, its tail is nearly indistinguishable from a person. A creature which uses an action to successfully make a DC 15 Intelligence (Investigation) check can see through this disguise.
Mimicry. The neptune’s harlot can mimic simple sounds it has heard, such as a person whispering, a baby crying, or an animal chattering. A creature that hears the sounds can tell they are imitations with a successful DC 13 Wisdom (Insight) check.
Slippery. The neptune’s harlot has advantage on ability checks and saving throws made to escape a grapple.
Surprise Attack. If the neptune’s harlot surprises a creature and hits it with an attack during the first round of combat, the target takes an extra 10 (3d6) damage from the attack.
Water Breathing. The neptune’s harlot can breathe only underwater.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 23 (4d8 + 5) piercing damage.
Sometimes called siren-serpents, these eel-like monsters have tails designed to mimic the appearance of a woman wearing a green dress, complete with vague waving and alluring sigh-bladders. They hunt alongside the rocky shores where they lay their eggs, which eventually hatch into tiny but razor-toothed serpentlings known as harlot-fry.