Featured on Equestria Daily.
Review by PaulAsaran

An Evil Lord learns of a forbidden spell that will destroy the world. Naturally, he intends to cast it.

No problem! Princesses Celestia and Luna will just send Twilight Sparkle to go stop him. That usually does the trick. There's only one catch:

There are only thirty seconds left to stop him before the spell is completed.

Inspired by Half Minute Hero