The Mad Hatter

You may choose not to untap Mad Hatter during your untap step.
{x}{r}{g}, {t}: Tap X target creatures. They can't untap until Mad Hatter does.
"If I had a world of my own, everything would be nonsense. Nothing would be what it is, because everything would be what it isn't. And contrary wise, what is, it wouldn't be. And what it wouldn't be, it would. You see?"