While losing to mill, on the last turn before they milled me out, out of desperation, I Karned for a Pithing Needle and named some Jace at random I didn't even know existed...
...and bricked their play, proceeded to attack for lethal.
Honestly, moments like these is why I play this game.
P.S.
I think it was very cool of my opponent to play out the card to show me that my play has actually won, instead of just scooping.