How to make good YouTubers bad

PewDiePie

 * Make all his videos about cream puffs

Markiplier

 * Have him show his Darkiplier face frequently

jacksepticeye

 * Make all his videos about sitting on a couch

iHasCupquake

 * Shrink her down to tiny size and keep her that size (that's impossible, though)
 * Make all her videos boring reaction videos

CinnamonToastKen

 * Break his webcam

JonTron

 * Have his account terminated

Game Grumps

 * Have their show cancelled

Egoraptor

 * Have all his videos about music