You take the blue noticeboard - the story ends, you quit the game and believe whatever you want to believe.
You take the red noticeboard - you stay in YAPP and I show you how deep the rabbit-hole goes.
(Actually, World 7 is painted grey. Anyway, it doesn't really matter.)
In case you are reading this without any idea of YAPP, here comes a short description for it:
YAPP: Yet Another Puzzle Platformer is a low-effort but well-designed puzzle game, with a casual but hard-core game experience, mainly inspired by Portal, Talos Principle and Braid.
Features:
[list]
[*]Seven new puzzles. Explore the potential power of the game mechanisms.
[*]New achievement / star not included. (World 7 is optional. You don't have to suffer from it if it makes you suffering.)
[*]A simple gamepad support. (Default key binding is for ps4 gamepad)
[*]1/5 and 1/10 timescale.
[*]Unity's default resolution dialog becomes available. (I have to admit mine is worse)
[/list]