YMMV / A World Without Rainbows

• Fridge Horror: It turns out the Sonic Rainboom helped prevent Fluttershy from cutting off her own wings.
• Harsher in Hindsight: The entire plot of the episodes revolves around someone going back in time to stop the Sonic Rainboom, which prevents the mane cast from meeting and becoming friends, and showing the effects it had. Guess what the plot of the show's Season 5 finale was?
• Squick: Sending solid, innanimate objects to an alternate dimension? Easy. Sending a pony to an alternate dimension? Fatal if done wrong. The first pony to try it "got a funeral on both sides" of the dimensional barrier.