Curious Homunculus // Voracious Reader (EMN) from Eldritch Moon, available at 401 Games Canada.

• Rarity: Uncommon
• Finish: Normal
• Artist: Filip Burburan
• Card Text:
  T: Add C to your mana pool. Spend this mana only to cast an instant or sorcery spell.
  At the beginning of your upkeep, if there are three or more instant and/or sorcery cards in your graveyard, transform Curious Homunculus.
  //
  Voracious Reader
  Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
  Instant and sorcery spells you cast cost 1 less to cast.