Goliath Daydreamer (Lorwyn Eclipsed)

Creature Ñ Giant Wizard - Whenever you cast an instant or sorcery spell from your hand, exile that card with a dream counter on it instead of putting it into your graveyard as it resolves.
Whenever this creature attacks, you may cast a spell from among cards you own in exile with dream counters on them without paying its mana cost.