Darth Sidious, Sith Lord

Ward {3} or sacrifice a creature you control.
{x}{t}: Darth Sidious, Sith Lord deals X
damage to target opponent or creature.
Dark Lord —At the end of your turn, search
your library for a {b} or {r} spell with converted
mana cost X or less, where X is the damage dealt
to an opponent by Darth Sidious, Sith Lord this
turn and either add it to your hand or add it to
your hand and untap X lands, then shuffle your library.