During your opponent's turn, when this card is sent to the Graveyard by the effect of your opponent's Spell, Trap or Monster Card, your opponent's turn ends.
Right away, my first thought upon discovering this card amongst my pile of extra stuff was that this could be really fun to use against Wind-Ups. I mean, it stops their loop dead in it's tracks even worse than Effect Veiler or Fiendish Chain can. However, there is the element of risk since it has to be discarded. But if you are successful with this card, just imagine how open your opponent might have left himself. Gives you pretty much an additional turn to do your things before the dreaded loop is attempted yet again.
While I doubt many will use this due to it's high risk scenario, it's certainly a fun card to use against Wind-Ups. So who knows?