For context, check out this post : https://gamejolt.com/p/an-abomination-of-shadow-has-escaped-and-split-into-several-sticker-cqjswxh4

About Shinies

Shiny Stickers are special variations of existing stickers that appear for short periods of time somewhat randomly. They are far rarer than regular stickers, and are considered collectibles.

Shadows

Shadow Stickers are stickers corrupted by a dark entity. It's origin is unknown. The Shadow Hunters (a special division of the Shiny Hunters) are committed to keeping our world safe from these extra-dimensional invaders! The Hunters are always eagerly accepting new recruits! Keep an eye out for future opportunities to join!