For me, its definitely Windslash/Telebracers.
There's been a game where my opponent randomly played Wind Slash and flipped my Telebracers, which got rid of a location I needed to seal in the win. He won that game based on that play.
On the flip side(lol), I've had an opponent Wind Slash on my turn, flipping my Telebracers and turning up the location: Mipedim Mirage. I used that mirage ability to win the game from there. I was playing a Gintanai deck and he had a creature in my back line that I couldn't get to. By getting that mirage, I was able to steer myself to a nail biting victory.