- [ The Multiverse Collision / TMC ] -

- Prequel: A flashback -

Summary: Nim, the original Guardian of the Tree of Feelings, was sent to the mortal realm in an Undertale Multiverse due to feeling unsafe around the other Guardians assigned to their own Tree, though upon arrival was attacked by a mortal who desired one of the Golden Apples fruited from the Tree. She took fatal wounds to the mortal, and after slaying them, created two brothers to become the new guardians; Dream, the Guardian of Positivity, and Nightmare, the Guardian of Negativity. Both were Skeletons, meant to be with the tree for as long as time, and each had an assigned role as a Guardian, one sole purpose: Protect the Apples. It was vital to protect this tree, as without it, all feelings in the multiverse would be lost. If one tried to pluck an apple from the tree with doubtful or sinister intent, the apples would rot and all become the same: Negative. Now, the Tree of Feelings bears two different types of Apples; Golden Positivity apples, said to make a mortal feel warm inside with the memories of wonderful dreams and the nicest wishes come true; and the Purple/Black Negativity apples, rumored (though never personally experienced) to leave your throat burning with the worst nightmares coming to mind and extreme paranoia following quickly. Though Dream and Nightmare had it easy, as no mortals ever traversed into the forest where they lived; life was peaceful. Though after several years, a small village sprung up around them with a white painted fence separating the two brothers from the village. After the Mortals got curious, they got a taste of the Positivity apples and couldn't get enough; using Dream to get happier, whilst harshly bullying the Guardian of Negativity just for the fun of it.

Nightmare had enough. At the age of 7, he wanted to prove he was just as good of a Guardian as his brother Dream, so he reached up and plucked a Golden apple from his brother's side of the tree and watched in horror as all of the apples turned black, Negative. His brother, Dream, in a panic watching from afar, bolted up to the tree and snatched the last Golden positivity apple from the branch before it could get infected. Nightmare had forgotten the most important reason for why this tree needed protecting; because without balance, all would be lost. In an act of desperation as the Mortals approached him with weapons like rocks and bats and pitchforks, Nightmare bit into the now negative apple and began to suffer the consequences.

Nightmare, falling to his knees, only had swallowed a bite of the apple before beginning to cough and tremble like an autumn leaf. A black substance drooled out of his mouth, leaking from his eyes like abyssal tears. Without warning, his pupils disappeared and his skull cracked in every which way; four gruesome tendrils protruded from his now ripped attire that fell to the floor soundlessly. Nightmare let out an agonized cry as the abyss took over his body, the sounds of his bones cracking and eyes rolling into the back of his head. A full minute of this passes by with the mortals stunned in complete horror, and Dream, his poor brother, watching in a stunned tear-stained silence.

The sounds of breaking bones and agonized whimpers and cries out for help died down, leaving nothing but an eerie silence at the black lump on the floor. Dream, with no hope in him whatsoever, whispered the name of his brother. "Nightmare..?"

In response, what was left of Nightmare began to stand and take the form of a corrupted parasitic monster with four large tendrils and a large, sinister, bloody grin. The left eye of this parasite opened, a bright blue eyelight scanning the faces of those around it. The tendrils then proceeded to rise, grow in size, and cut the Tree of Feelings in half; devouring ALL of the Negativity apples and going on a wide murder spree to kill all that ever tormented him in the past. Dream stood there helpless, watching in defeat as his beloved brother wreaked havoc on his home. The parasite, once it had finished, approached Dream with that similar sinister grin and opened its mouth. "I believe that belongs to me," whispered the parasite, eyeing the golden glow beneath Dream's gloves. With a small cry out, "NO!", he took a step back and devoured the positivity apple. It fused with his very own soul, marking himself as a target to this parasite before him. It approached him, its grin fading away and its amused stare turning into an annoyed, merciless glare. "I'll kill you," he said with a sudden playful smirk. "I'll murder everyone you love right in front of your very eyes."