The Watcher

Devoid, Firststrike, Double strike, Trample, Flying, Vigilance, Hexproof
Every time you play a creature, sorcery, enchantment, or instant, The Watcher gains indestructible until end of turn.
{2},{t}, Creatures target opponent control cannot block Demons or Stalkers.
{1},{ut}, Search an opponent's library for a card, reveal it, and play it without paying its mana cost.