The Doctor sighed, glancing over at the now teenage-mare.
He put a hoof atop her head, giving her mane a ruffle before arising from the bed, and walking into the kitchen.
"Hey, Doctor? I think it's ready, it's all bubbly and golden like you said..." Ditzy said, staring into the clear, glass bottle that had been clearly made for potion-making.
The stallion must have great trust in the wall-eyed mare to let her mix up this complicated brew.
"Ever so carefully..." The stallion lifted the brew in his hoof, walking it over to the sleeping mare.
"..Hm..huh?" The mare stirred as the potion was brought to her lips.
"Shh...Shh...Just drink this...It's okay...Shh...." The mare slurped down the liquid, feeling a tingling, warm sensation fill her body as she fell back asleep.
"Good... She's asleep. Now, Ditzy, how would you like to accompany me into the mind of this young pony here?"
The Doctor stretched out a hoof, and Ditzy took it.
"Don't mind if I do!" The two touched the young ponies cheeks with their hooves, then felt themselves be...evaporated, would be the word.
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The two awoke, hearing the sounds of strange, singing birds as they flew by in a flash of silver.
"Oh...Celestia...Where are we?" Ditzy arose from the ground, the Doctor already up and about.
"Well...We appear to be in the very far past of Miss. Unseen's mind. Or we teleported into an alternate universe that looks quite like my old home in Gallifrey..."
"Gallopfrey?"
"No, Gallifrey. What Is It with ponies and these puns?"
"What are...Puns?"
"Oh, never mind."
They wandered throughout the vast and wonderful scenery, only to hear the sound of hooves-on-grass to hooves-on-stone.
"Doctor-" Ditzy began, only to be interrupted by the stallion himself.
"Ah, here we are! The main hallway! Let's see....Childhood....Secrets....Important Memories...Significant Memories?" The Doctor curiously furrowed his eyebrows at the door, obviously it lead to another hallway, of which they were definitely going down.
"Hey, Ditzy! I think this is it!" The Doctor swung open the door...Only to find....
A brick wall.