Author's Note: Because why not rewrite Undertale with a magical Frisk? This fic originally started with the question "What if Frisk was more like a Ravenclaw," and then my mind wandered. I'll admit right now that other than a few vague ideas, I don't have much more planned than the Ruins, but I wanted to upload this before I lost the files or something.

For the record, this fic won't actually have Harry Potter characters in it but it will use terms from the Harry Potter series. Characters may be mentioned though.

-Midnathething

Cautiously, Frisk peered into the gaping hole in the mountain. They knew that they shouldn't be there, the legends were clear enough about that, but they'd just been so curious and here they were. Did monsters really live under the mountain? Their current foster parent, a Squib with a strong distaste for magicals, seemed to think so.

The child shook their head. They were already in trouble for accidental magic earlier that day, staying out too late would only get them in more trouble... It would be a long hike down the mountain and they'd need to leave soon if they wanted even a sliver of a chance of getting home in time. The child turned to leave but found themselves stumbling when their foot caught on a root.

With a startled yelp, Frisk took a few steps backwards in an attempt to stabilize themselves, forgetting about the gaping maw behind them for a few moments. They immediately found themselves wishing that they had just scrapped their knee because instead of falling a few feet they found themselves tumbling into the hole with a panicked wail.

The child's mind shut down for a few moments, leaving them with nothing but blind panic and the knowledge that they were probably about to die. The ground, they realized, was rapidly approaching. Before Frisk had even fully processed this realization their magic seized a hold of their body. They bounced, once, twice, then landed in a bed of golden flowers, breathing frantic and uneven.

The child took a few gasping breaths before they lost consciousness.

. . .

When Frisk regained consciousness they found themselves laying somewhere surprisingly soft. Where were they? The child sat up, groggily rubbing their eyes while they looked around. Everything rushed back at once, getting in trouble for an incident with accidental magic, running away, deciding to explore the mountain, finding the hole, falling... Frisk gasped quietly. How had they survived?

Their eyes widened as they looked around. The room was dimly lit, the sun's rays struggling to reach deep into the mountain, making it difficult to see anything other than the bed of golden flowers they were laying on. In the dim lighting they could make out the vague shape of a tunnel leading further into the mountain. A quick glance around the room as they pushed themselves to their feet revealed that it was the only way to go.

Frisk took a couple calming breaths, wincing when bruises on their back pulled uncomfortably, grabbed a stick - conveniently close to wand size - that lay near where they'd fallen, and began to move towards the tunnel. When they reached a wall they leaned on it, using it to help them regain their balance and guide their path while their eyes adjusted to the darkness. A beautifully carved doorway came into view and the child paused to take in the sight.

"Guess something lives down here after all." They murmured to themselves before continuing

The next room was surprisingly bright and Frisk moved a hand to shield their eyes. They stopped, giving their eyes time to adjust.

"Howdy!" A small voice chirped.

Frisk tensed, searching for the source of the voice. Their brow furrowed in confusion when they found it. A... Small yellow flower?