Author's notes: My first fanfiction, written right before the Grand Finale. Based on an idea I had some time ago and a bit of an experiment, but hope you will enjoy it anyways.

"Look there, another pretty one!" Mabel yelled and ran to the flower to pick her up. Dipper just sighed while he walked behind her.

Mabel got suddenly the urge to make wreaths of flowers, and of course she drafted her brother into that. He wasn't very excited about that, but it isn't like he would let his sister go alone in the forest. And he had nothing else to do anyway. So he could at least try to have some fun for his sister's sake. For this trip she decided to wear a white sweater with a little lamb on it.

At least he could avoid some drudgery in the Mystery Shack, that always happened when grunkle Stan thought Dipper had too much free time. At least grunkle Stan didn't protest them walking in the forest, only asking them not to bring any animals or cops back.

Mabel already had a hand full of flowers, but seemingly not enough for her. Every few minutes she gushed about a new type of wild flower she just found, and asking Dipper if he could identify it. When he knew, he started to rambling about the name and details of it's species. And when he didn't, he just looked ashamed for a moment and was silent.

They did already wander deeper in the forest like they usually did. The vegetation began to get more sparsely and the ground to get more rocky while they walked uphill.

"Want to play I spy with my little eye?" Mabel asked, humming a song while she surveyed their surroundings. "Mabel, I don't want to-"

"I spy with my little eye something...green." Dipper just groaned and ducked under a branch. "Let me take a guess" he said, without even taking a look around "it's a leaf."

"You're right!" she burst out, "Yaaay! Now it's your turn, bro-bro." He just sighed and took a look around, scanning his environment. The ground somehow looked darker than before and the grass was growing more sparsely, in single blotches instead of a thick carpet.

"Mabel, can we please not." He tried to keep a serious tone and face, but couldn't hold when he saw his sister sticking flowers into her hair, so he closed his eyes.

"That's no fun, you must keep your eyes open. You never know what you might find. Look, I spy with my little eye something...rainbow?" Mabel's voice was suddenly filled with confusion.

Dipper immediately reacted when he noticed that something was off with his sister. He opened his eyes and watched her make her way through a bush. "Mabel, be careful" he shouted worried while he hurried at her side, thorns tearing at his vest.

"Don't worry, look what I just found" she said and picked something up. Dipper came closer to investigate it, ignoring the thorns and the question how her sweater got undamaged through that thicket.

She hold something up that looked like a yellow-brownish scale, but the sunlight refracted at it, making a rainbow shimmering over it. "Oh, it's so beautiful! I'm gonna keep it for my scrapbook!" Mabel said, jumping happily up and down.

Dipper grabbed it and inspected it closely. "But what is it? It seems to come from a reptile, but I don't know any reptile that lives in Oregon that has scales like that." It was as long as his finger and about twice as wide. He hold it against the sunlight, looking at the reflections.

There was suddenly a deep growl, more of a buzzing that you felt with your body than you really heard. "What was that?" he asked, furrowing his eyebrows. "The voices in your head." Mabel chirped to answer him. He just gave her a glare before he closed the eyes, trying to locate the source, but it was in vain. It had vanished as fast as it appeared.

He sighed and hold the scale out where he expected Mabel to be. "Maybe we should head back home. I don't know what's out there, and this part of the forest is definitely creepy. And I don't have the journals with me, great uncle Ford needed them for his work." He made a small pause, before he thought of something to convince her. "Hey, at least we got a souvenir and we can ask great uncle Ford about it."

He opened his eyes, startled that Mabel wasn't there where he thought she was. Instead she was scouring in a bush, with Dipper only seeing spots of her white sweater through the green. "Found another one!" she triumphantly exclaimed while she hold another of the scales up in the air, a ray of light breaking on it. Dipper opened his mouth, but was interrupted by Mabel again screaming. "Look at this, Dipper!" She pointed somewhere behind the bushes, before she disappeared in the green leaves.

Dipper got closer, trying to see what she discovered. He made his way through the thicket. Holy Moses, how does her sweater doesn't get reduced into a tangle of yarn here? As he came out on the other side, he looked on Mabel and was shocked.

His sister was standing on a patch of churned earth. Dipper wrinkled his brows, while he investigated what clue Mabel found there. "Look, there are more over there! We found a trail!" she exclaimed proudly. "You're right...", Dipper said absent-mindedly, while took a closer look at the ground, handing her the scale he hold.

"And you wanted to go back to Ford, bro-bro." His sister said, forming a mischievous smile. "Giving up so easily? Just imagine what the author of the journals would say about that?" She teased him. He gave her just a glare and sighed then, relaxing. "Okay, let's go find what lies at the end of this trail!"

"That's what I wanted to hear, Detective Dippingsauce!" she happily obliged and started following the marks in the earth, while Dipper took a closer look at everyone of them. "Don't walk too far ahead." He said, while he tried to deduce some information from the marks his sister found.

It seemed like whatever caused them had big claws. That wasn't a big surprise, if that being was indeed a reptile. But some of the marks were...odd. The earth seemed moved by something that had a clear source of origin and distributed it's energy uniformly, like a shock wave.

He tried to make sense of that, but he had no idea. Did the feet of the being crash so hard on the ground that it created a shock wave? Was that the deep growl they heard? He sighed and tried to catch up to Mabel. She went ahead and he didn't want her to stumble on whatever was this alone.

"Mabel, wait for me." He called out. He saw her again kneeling in front of a tree, looking behind it. "Come on, that scales aren't gonna run away." But she didn't react, she just stood there.

Noticing that something was off, he rushed to her side, worried about what she saw. He carefully made it to her side, cautious not to startle her or whatever she might be looking at. As he reached her, she gave him a quick look, before she silently pointed at the cause of her marvel.

Dipper had been right that it was a reptile, and he was sure that there was nothing like that in Oregon, and probably the entire World. Well, except for in Gravity Falls, of course.

It resembled a monitor lizard, but was several times larger than the biggest one Dipper had ever seen. But there was a big, spiny crest on it's back. While the rest of it's body had the same yellow-brownish tone like the scales the twins had found, the crest was fiery red. He wasn't very keen to see how aggressive it was. In these woods everything could be dangerous.

"It's beautiful!" his sister whispered. And he had to admit, there was a certain grace to that creature. Currently it was laying down on a big rock, letting the sun shine on it's back, where it basically emitted a rainbow over itself. She started making her way silently around the tree. "Do you think it's friendly?"

"Mabel! Let's not scare it!" Dipper hissed to his sister. He was worried that she would trigger a fight-or-flight-response for that lizard, and in Gravity Falls he couldn't even count on the flight response being safe for them.

"Don't worry, Dipper! I'm sure it's just a big cuddly lizard!" Mabel chirped but Dipper laid his hand on her shoulder, holding her back. Which may have been for the best, because something else seemed to startle that lizard.

There was again a growling, but different from the one they heard before, not as loud and more in the audible spectrum, and there was certainly no doubt that the lizard was responsible for that. The crest stood up on it's back, glowing like magma that just broke out of the earth. Dipper heard his sister gasping because of that breathtaking spectacle they just saw. He had to admit that it wasn't something you saw everyday.

And then it happened.

And then, another deep growl, like the one they heard before. Dipper felt his body shaking, but he didn't even notice it really because he was more focused on what his eyes where seeing.

A yellow flash of lightning shot from the lizard's maw and hit something in the woods, obscured for the twins by the vegetation. But they still saw dirt and splintered woods flying around. Now they knew what the cause of these growls was, and it was better not to make this lizard feels threatened.

Mabel shrieked of fear and surprise and Dipper felt her hands clinging on his shoulder. He grabbed her, both to calm her down and to reassure himself that she was there and safe. He was slowly pulling her away, both of them looking shocked at that dangerous being. It didn't seem to notice them or at least didn't saw them as a threat. It's crest was already deflating, and Dipper was happy about that, now only thinking about getting his sister to safety.

Everything was fine, they were taking slow steps back and Dipper noticed he had hold his breath. He already exhaled in relief as he noticed the lizard's crest standing up again. He didn't even wait to see what if they were the cause of that or not.

Dipper just screamed "Run!" and pushed his sister downhill the way they came from. They first heard the quieter growl, and then they both heard the deeper growl, or better said, felt the deep growl in their bodies. The tree they hid behind them fell as it's trunk got obliterated. Hot splinters shot in all directions and a loud creaking announced the falling tree. With a diving jump Dipper pushed both himself and his sister out of the way.

With a shattering sound the tree crashed behind them on the ground while they fell to the ground. But there was no time to waste, as they already heard another of that growls that preceded every of these lightning strikes. Mabel was faster in standing up and pulled on Dipper's arm, heaving him on his feet and they started running again.

Dipper didn't dare to even glance behind him, focusing solely on the path before him, but he already had seen the lizard attacking twice and out of pure reflex when it was again time for another strike he again pushed his sister away and threw himself both in front of her and hopefully out of the way of the lightning.

He was right, where they stood a mere moment ago was hit by a lightning and they both were shocked by it's thunder. Dipper could feel the shock wave painfully rumbling through his body, and the sensation of hot air blowing over them. He just hoped that Mabel wasn't hit by whatever that beast shot at them.

They were tumbling downhill, rolling over each other. The twins hold onto each other, out of pure reflex to protect each other. While it was very painful rolling a hill down, it at least brought them away from the danger.

When they reached the end of the hill, Dipper was landing on Mabel, a pain surging through his stomach. The flowers she had collected were flying around them like floral confetti.

He was rubbing his head. "Ugh, Mabel, you're okay?" He blinked several times, trying to get the dirt out of his eyes as he heard it.

"D-d-dipper." Mabel's voice was trembling with shock and fear. All pain and discomfort was quickly forgotten. He looked at her, her eyes going wide as like they wanted to leave her head. She looked down on herself and then Dipper saw what caused that reaction.

He felt his guts twisting as he looked on that. "No, no no nonono." he breathlessly stammered as like he couldn't accept that as reality. The white lamb on her sweater was coloured red. "Mabel..." he said, looking for words, his head empty of any thoughts.

"D-dipper, please." She said again, her voice now filling with concern. "D-don't worry." He said, trying to calm her down. "We can take care of that, everything's going to be fine."

"But..." she tried to grab him and threw him off. "It's not okay! It's not okay!" she started to frantically scream.

"Mabel, calm down!" he screamed back, trying to pin her down. He better should follow his own advice because his own voice was shacking with fear and pain. He tried to grab her wrists and pin her down, because she started to frantically flail around, and might hurt herself with that.

"Don't move, you're just gonna make it worse. I take care of you." He felt his limbs go numb, he didn't know what he could do. Just the thought of the red blood on her sweater filled him with dread.

"NO!" she screamed again. She wrestled her arms free. "No, you don't understand. Dipper!" Her eyes felt with tears and her voice with desperation. It hurt his heart to see his sister like that.

"Mabel, calm down. You're injured, you just need to calm down!" She overpowered him, she was just stronger than him and grabbed both his wrists, shoving him off her. She pinned him down on the ground, with more force than was necessary. He felt a sudden surge of pain in his back, he inhaled sharply the cold air.

His face distorted in confusion as he tried to comprehend what was going on, while Mabel was now lying on top of him. Her tears was trickling down on his face. "Please Dipper, let me help you."

Dipper looked down on himself, and the reality dawned on him. There was blood on her sweater, but it wasn't hers.

It was his.

He was right that he was in front of her when the lightning struck.

He successfully protected her from harm.

His shirt was ripped, and what was down there was a mess.

He didn't even want to look down there, because just a simple glance made his heart racing. He already felt the cold spreading through his body, now with the adrenaline subsiding. Mabel was screaming at him, grabbing his shoulders, but he didn't understand her. His head was getting cloudy and he felt his vision fading.

He tried to focus his thoughts, but it was a losing battle. A last moment of clarity allowed him to see one of the flower's Mabel collected lying beside him and hear the last words "Dipper, please, don't leave me, please..." before the darkness got him...