Darth Sidious, Sith Emperor

Hexproof, menace

{u}{b}{r}, {t}: Gain control of target creature an opponent controls. It becomes a Sith in addition to its other creature types. Activate this ability only if you control no other Sith.

At the beginning of your upkeep, if each opponent controls no creatures, you win the game.

"Now you will experience the full power of the Dark Side."