Enigma Spellcaster

When Enigma Spellcaster enters the battlefield,
exile target instant or sorcery card with
converted mana cost X or less from your
graveyard, where X is the number of instant
and sorcery cards in your graveyard. You may
cast that card for as long as it remains exiled
without paying its mana cost.
"I have learned many a lesson on my travels,
an important one is lightning hurts" -Heploix