No land is a perfect land. There could never be one. Between strife and conflict, peace against violence... all that lands could truly do was just to be better, not worse. Then what brought about Gensokyo? A magical land once thought to have harbored countless youkai with their own goals and deeds. Yet something; sometime; somewhere, went wrong, and now the once "Land of Illusions" became nothing but a nightmare to live in- no, it wasn't even living there, it was surviving. Every day had danger to it, and one without any was merely a waiting process until there was. There was nothing positive that came from the apocalypse: Most died painful, less painlessly, and not a single soul across Gensokyo would ever feel safe again. If it wasn't clear it became a physical version of a bad dream, it would never be. What was the main source of this?

Variants.

No one ever knew where they came from, though most are (obviously) aware that they are the main threat in Gensokyo now. Variants were the nightmarish, mutated versions of the residents and creatures of the land, often leaning towards their traits. The lunar rabbit girl that was Reisen Udongein Inaba, physically grew into that of a monstrous bunny, among other changes, which was just one example. Only few influential figures became Variants; their power didn't need to be described for what potential destruction they could bring. However, it was the common ones, such as the playful and neutral fairies becoming aggressive and cannibalistic, turning on their own, that brought a greater amount of pandemonium than them. Everything happened so fast on the first day.

...

...

The Hakurei Shrine was still. Quiet. Had there not been the idea of Variants, the gentle breeze of air without other noises to compliment it would be terrifying on its own. Now the only remnants of their influence were the old blood stains of Suika Ibuki, Kana Anaberal, and Remilia Scarlet. Long since the tea party there had happened and had been interrupted by a late guest. There was nothing of importance to the shrine anymore; as if it's god (or any other shrine god in Gensokyo) had abandoned everyone left there. Despite the peace, would one here truly trust that would last long? Worse yet, if that "peace" was even a real thing? But it was rare, so surely it could be here now-

"kachikachikachikachika..." Were the noises that began to blend into the shrine's proximity. The idea was quickly disproven. From the open door of the shrine, stepped out Reimu Hakurei... or worse, Variant Reimu. Along clicks and clatters and the sound of repetitive footsteps, the creature didn't rotate her head or anything, simply staring out into the stone path exiting the shrine area, silent. Normally, she would be off and somewhere else to hunt those closest to the true Reimu that she failed to kill, but... whatever brain she had, felt as if there was a need to roam here. Almost like a zombie, Variant Reimu stepped onto the grass and began to roam around. Monstrous killer she was, though she had the intellect to conserve movement for when she finds movement. She stumbles around, searching, searching, searching... but what is she looking for?