Miasmic Sands

Misasmic Sands is an artifact in addition to its other types.
As an additional cost to casting Miasmic Sands, discard an instant or a sorcery.
Enchanted creature gets "{x},{t}: where X is the converted mana cost of the card discarded with Miasmic Sands, minus the Enchanted Creature's converted cost: Cast a copy of the spell discarded with Miasmic Sands"