Rainbow Dash talked with Trixie, telling her about all the wonders she and her friends did with their powers since they had found the geodes, years ago. Between Rainbow’s super-speed, Fluttershy’s animal friendship, Sunset’s telepathy and Twilight’s telekinesis, Trixie wondered what powers would she enjoy, now that she finally had her own magic-induced transformation. Of course, Rainbow Dash hid the fact that she didn’t know what powers her own mermaid form had, or even if it was permanent. Certainly, Rainbow right now had no super-speed, nor super-strength and certainly no magic rays so far, but she was not going to ponder on that fact: Rainbow had now her own convert, both in body and mind.
 
Rainbow Dash, however was still very torn inside regarding what she had done during the day. In retrospective, she was ultracompetitive, and that trait made her envious sometimes, she could not stand being left behind. She also tended to overthink things in her own way and let herself be carried away by said obsessions. Some years ago she even stole a boat to go find “Evil-Magic” and ended up in a quicksand pit, alone and lost on an island. If it were not for Sci-Twi and Sunset, she would have perished there, if not drowned in quicksand, then devoured by a carnivorous plant. She was right in the end, though. The evil magic was real. She convinced herself to always trust her gut-feeling. And her gut-feeling was very schizoid today… she had felt absolute despair at losing her legs, and a lot of leg-envy of all the women that still could walk, not to mention her plans for the future… winning a championship in sports, winning a marathon, graduating from college, have a bright career… find mr. right and start a family of her own… people tended to confuse her tomboyish behavior for full-blown attraction for her own gender, but in truth… Rainbow Dash longed to have, eventually her own children. Was she even able to reproduce now? Would she need to transform a man to love her? Was the curse even able to affect males, or just females? Would a man be turned into a merman or a mermaid? and most importantly, wasn’t the fact of transforming somebody against their will, just plain evil? NO. NO. NO. She was not evil, she rationalized. She was the R to the D, she was the Element of Loyalty. Trixie loved being transformed. Rarity was just being her dramatic self, yeah. She was not a villain. Or was she? Rainbow was absolutely introspected, while still swimming along Trixie.
 
They swam for several minutes, searching the bay to find the Illusions, Trixie’s band-mates and friends: Fuchsia Blush and Lavender Lace. Those girls were spending the day scuba diving near the reef. Finally Trixie found them near the edge of the reef, before an open ocean plain. The depth of the water was deliciously warm at 6 meters deep and there were no currents, this zone of the Caribbean was perfect for scuba-diving. Rainbow Dash waited and kept thinking, as Trixie approached her friends.
 
Fuchsia and Lavender were placidly looking at some corals when Trixie announced herself, in her best bombastic voice. She loved to be able to talk and breathe underwater, it made her feel so unique and powerful.
 
“Behold, fellow Illusions! Turn around and see, you band leader! The Great and Powerful Trixie! Master Mer-Magician of the Seven Seas!” said the white-haired mermaid, striking a pose. Fuchsia and Lavender turned around and almost fainted at the sight. Their best friend stood (so to say) in front of them, wearing only a seashell-bra and sporting a mermaid tail, gills and an angler antenna. They screamed in awe but remembered they were underwater. Both contemplated in awe.
 
Trixie was pleased, and swam slowly, letting them gaze at how flexible she was and convincing them she was not wearing a suit. Her tail bent at angles her former legs and knees would never allow for. She got closer to them, smiling.
 
“That’s right, my friends, The Great and Powerful Trixie has found the secret for authentic sea-magic! Trixie can breathe and talk and live underwater, and now has a lot of ideas for the best show in the Seven Seas!” Lavender tried to say something, while pointing at Trixie’s waistline. Her eyes went from the tip of Trixie’s tail-fin, to her peduncle, all along her length, to her waist. Fuchsia was just in awe, her eyes fixed on the impossible mermaid in front of her.
 
“Hahaha, fear not, my dearest friends, for I do not bite nor hurt! I have come to you, searching for your help! Let us Make “Trixie and the Illusions” Great Again! I will bestow upon you my magic, and you can join me at the sea, if you so wish!
 
Again, for obvious reasons, nor Fuchsia nor Lavender could respond in words, but Lavender nodded and pointed at Trixie’s tail. A small smile was visible under her respirator.
 
“Ah, wise choice, my dearest Lavender! Allow me to touch you to give you the mermaid gift, that way you will never again need a respirator!” and with that, she extender her arm and hand and caressed Lavender’s cheek. Immediately, the girl’s skin glowed in a warm, golden light and the transformation began in earnest.
 
Lavender felt six tingles on her neck and a cutting sensation, it was not painful but just strange and deep, as her gills appeared. She suddenly felt how the seawater started pouring directly from her neck into her lungs. She dreaded the sensation of being drowned but instead she felt oxygen-rich water filling her chest. Her respirator suddenly was uncomfortable and she pulled it from her mouth, taking a long deep breath of water. It felt so good, so natural. She looked downwards as her feet exploded in size, no pain at all. Her toes grew and now were morphing into fin-rays while a strong webbing between them formed immediately. She instinctively joined her ankles and they fused together, followed up by her calves. The transformation crawled up her legs, turning them yellow. Thousands of delicate scales grew through and broke free of her tender skin. She felt tingles at her forehead, signaling the development of her own angler. Her waist felt itchy and slimy as a belt-like fin formed asymmetrically, enveloping her slim figure. The closing ends of said fin connected just above her bikini line in her pelvic region.
 
“Whoa! This feels amazing! Strangely arousing too! You should try it Fuchsia!” Said Lavender as she could now talk underwater. She laughed as her bikini bottom started melting away and her thighs kept fusing. “This feels so good! Do we have a three-day-time-limit or something? Because I could use a month or two away from the “New-Normal” life, if you know what I mean”
 
Fuchsia removed her own respirator, looked at Trixie and beamed in glee as she swam closer to her band-leader. Trixie admired her handiwork with Lavender and made a gesture to Fuchsia, inviting her to touch the arm, she smiled back at her friend. “So, Fuchsia… what do you say? Do you want to partake in the fun here, down where it’s wetter?” As Lavender Lace transformation continued, Fuchsia Blush moved her hand, closer and closer towards Trixie’s inviting hand…

The ones with Twilight aren’t anywhere to be seen.