Well there was more pregnancy stuff in need of doing at the time.

Cadance didn't take the reveal of Celestia and Luna's true natures very well, terrified of the idea that she, by relation to her foster aunts and having become an alicorn, might be a monster herself without even being aware of it. She retreated to the Crystal Empire to reflect upon events, and in her meditation she received visions of a mysterious pony who claimed to be her predecessor Gradually lulled into following the desires of this unknown princess, she was tricked into releasing Amore from her imprisonment, who fell upon her and revealed that she was her ancestor, and her eldritch blood flowed through her, allowing them to communicate. Amore thus resumed rule over the Crystal Empire, and Cadance completely lost herself.

This was the general impetus I'd had for a while for Cadance's backstory in the eldritchverse, but I hadn't been entirely certain about her actual design. I had on the side felt the yearning for a monster akin to the Joy Mutants from LISA, but I hadn't really known what I could DO with that on its own, not wanting to make a whole new setting for that or a single character that can't do much, so instead I thought I could use it for the eldritchverse instead, in hindsight though I'm not so sure how well it works since it seems kind of plain in comparison to the other designs. The concept with Cadance is that she's not so much pregnant in the same sense as Rarity had been seen previously, rather that she is filled with a piece of Truth, a roiling mass of raw life energy which can be molded into any possible form.

Full res available here: https://derpibooru.org/1329342

My Little Pony as a whole is owned by Hasbro.
Original art by  mr.pink, colors and such done by me.



I don't know yet if/how Flurry Heart might fit into the eldritchverse but I suspect it's going to be tragic.



Being too big to reasonably move is just a better reason to seclude oneself in a cave.