Reclamation: The Pool Of The Forgotten
As the newly minted sphinxes lay slumbering, events unfolded in a very different place.

A hawk’s talon and a wolf’s paw shaped a pair of clay sculptures in front of a pool of swirling light.

Tinted eyes watched as a pair of familiar mares, a unicorn and a pegasus took shape.

A snaggletoothed smirk. A snap of fingers, and the clay became flesh and bone.

At the same time, the pool of light bubbled up, and two crystalline orbs the size of grapefruits were launched out of the pool and towards the bank where Falak Disc worked.

Falak attached loupes to his unicorn horn and eyed the crystals carefully before he laid them on pedestals in front of the two.

He had to make sure the right memories from the Pool of the Forgotten were in the right mares, after all.

Satisfied, Falak channeled his magic into the altar, and the crystals dissolved, streams of light entering the slumped ponies.

Seven minutes after the deed was done, the bodies of Courage Fire the unicorn and Starlight Twist the pegasus opened their new eyes.

“Wh...what happened?,” Courage asked no one in particular, to which Falak replied, “You saved the Sphinx race. As a consequence, your old lives were washed away, into the pool behind you.”

Twist looked at the pool. In it, she saw snippets of the journeys of Clover The Clever as he pursued a sorceress, and above it, she saw Queen Starlight Sands and First Consort Desert Courage slumbering happily.

“The Pool of the Forgotten,” Falak remarked. “Home to every memory no mortal means could ever hope to retain. It is here I shaped new bodies for you, identical to those of who you were before you entered that pyramid and accepted the charge of the Sphinxes. From the Pool, I called the memories that sloughed from the newly named Desert Courage and Starlight Sands. With those memories, I shaped you back into who you were, shaped new souls to inhabit your bodies.”

“So, what you’re saying,” Twist said, “is we’re copies of the ponies that turned into those two Sphinxes, crafted because...?”

Falak waved his paw. “It seemed a shame that your journey had to end just because you took a cause without knowing every effect. Now everyone’s happy. The Sphinx get their litters, and you get to keep being you. Toodles!”

He snapped his paw, and they were returned to the mortal plane.

Falak sighed. “Some days, it’s depressing to just sit here, but a happy ending is a happy ending.”

Author's Note

I conceived this after reading Riddles And Whispers by Honeydrops.

Basically, it shows an in-depth process concerning the same thing as Elytra getting his Honor Guard: call and direct the memories, provide the body, and you can bring back ponies who had their memories of their entire life removed and/or replaced by some transformation or other.