Manta (mermaid)
Manta is the eldest sister of the mermaids Tentacle, Anemone and Urchin, and stepsister to Remora. She's mentioned during the The Mermaids and the Dragon lore.
Manta and her sisters lived in their home in the Blue Spiral, where they left Remora every hunting season to clean and take care of the house since she still didn't have magic. After a thirty days long season, they returned home to find that Remora had left the house and escaped from her oppressive stepsisters. Since none of them liked the idea of having to cook their own food themselves, they immediately set out to find her.
After a few days of searching, they came to the coasts of Asgarnia, where they used their magic to transform their fins into legs so as to better search for Remora. As they walked through forests and hammocks filled with sleeping men, they found Remora's footsteps leading into a cave in the shoreline. Heading inside the dark, vast cavern, they walked onto a platform from which they could sense they were not alone. Calling out for Remora, the cavern shook with a ferocious roar before a glowing mechanism gave them enough light to see an enormous dragon before them, it's mouth larger than a whale.
Surrounded by its mouth, the mermaids could hear a voice telling a story of how it would find time to sing in its sister's home, even though it knew they would silence it if they knew. Convinced that it was Remora and that she had finally gained her magic, which somehow transformed her into a dragon, they were filled with disbelief and jealousy at her. As they contemplated her, though, the dragon started taking a breath to spit fire. Immediately sensing the danger, the mermaids jumped backwards into the water, but they were magically suspended in thin air as time seemed to have stopped. In a desperate attempt, they surrounded themselves with the water below using their magic just as the dragon spat out it's fire breath at them. With the water aropund them boiling, they started to burn before time resumed it's flow and they fell into the lake, shrieking in pain.
Manta's sisters survived and escaped, though she wasn't so lucky. Her sisters wrapped her corpse in kelp and decided to bury her before searching for a way to gain powers greater than Remora's and becoming dragons like her. None of them ever realised Remora was not the dragon, but inside the dragon.