Kelpie

Kelpies were creatures that resembled a mass of seaweed.

Description
Kelpies could alter their form to appear as either a woman, a hippocampus, or a green horse. But regardless of what form they took, their substance was still green seaweed and other creatures could often identify this in broad daylight if other magic wasn't utilized to enhance their deception.

Personality
Kelpies were often confused when confronted with victims that were immune to or incapable of drowning, but not hostile towards them. Rather than dismissing them, kelpies would welcome the charmed victim's continued protection.

Biology
These creatures reproduced asexually, increasing in size to and then splitting into two or four more kelpies. This could be done once a month so long as they were plentifully fed. Young sprouts were incapable of casting any spells. If properly cared for, a sprout could grow into a full-sized kelpie within a month.

In either their human or horse form, kelpies could roam about on land for upwards of three hours.

Abilities
These creatures were capable of casting the charm spells and could communicate telepathically with any being by embracing them. However, their charm spells were only known to work on humanoid males. The effects of a kelpie's spells would end shortly after its death.

Their bodies were largely invisible in the infrared spectrum. Due to consistently being drenched in water, fire-based attacks were often ineffective against them.

Combat
Kelpies had no straight offensive abilities outside of their shape-shifting and charm humanoid males into thinking they were in trouble and needed rescuing. Upon the person attempting to rescue them, kelpies would grapple their victims and hold them in the water until they drowned. If a kelpie could not reach their victim, then they would lure them into swimming towards them until they drowned. Once a victim had died they would drag the body back to their lair.

If attacked, charmed men would fly into a confused rage and attack those who harmed the kelpie.

History
Between -215 DR and 750 DR, the kelpie population within Serôs nearly went extinct due to over-harvesting by the realm's merfolk. Eventually their population recovered along the Sea of Fallen Stars's coastal shallows.

In 1361 DR, the illithid Vestress used the human Dagmar to plant kelpies in the water in her attempt to conquer the island of Ruathym.

In the month of Marpenoth, 1369 DR, Iakhovas used his magic to summon some monstrous elder form of kelpie all around the Whamite Isles. He used these kelpies to draw the entire population of the Isles into the ocean, drowning and reanimating them into an army of sea zombies.

Rumors & Legends
One legend claimed that kelpies came about because some vengeful deity of the sea wanted to punish men for being so rash as to sail their domain without giving them proper observance. This legend tried to explain the immunity of women to the charm abilities of kelpies as being because there were so few female sailors at the time of their creation.

A less widely-known legend tells of kelpies having been created by the archomental Olhydra, who made all women immune to their charms out of respect for her sex.

Society
Kelpies lived largely solitary lives.

Diet
Being plant creatures, kelpies largely obtained their nutrients by means of photosynthesis. However, they were also known to feed upon the bodies of their victims.

Homelands
While kelpies could be found in almost any climate, being very adaptable creatures, they most preferred to inhabit the oceans of temperate or tropical regions. They were usually encountered within the first depth of the ocean layer. Outside of oceans, they were known to be found underground or even within artificial bodies of water.

Following the Twelfth Serôs War, kelpies were known to be found deep in the ruins of Alsyrrt. Some were also known to be found in Maztica, the River Ashaba, and Dragon Reach.

Outside of the Prime Material plane, kelpies could be found in Draga Salt-Biter's domain of Saragoss in the Domains of Dread.

Relationships
Other fish and aquatic grazing creatures generally perceived kelpies to be mere seaweed and would eat away at their bodies. In Serôs the kelpies were thought to fill important niche in the sea's ecosystem as their natural scent acted as a repellent to sharks. Hunters would often seek them out in hopes of gaining some of that protection for themselves.

Some kelpies were known to ally themselves with powerful creatures and would act as guardians for submerged treasures. One such example was the marid Kalbari al-Durrat al-Amwaj ibn Jari, who had kelpie servants in her Citadel of Ten Thousand Pearls.

Use
Kelpie sprouts generally fetched upwards of around 500 gp.