Shifting Tides of Mana

As an additional cost to cast Shifting Tides of Mana, exile five cards with a converted mana cost of 5 or greater from your graveyard.
{1}: Choose one: • Add one mana of any color to your mana pool. draw a card.
• Gain {e}{e}. Tap or untap target creature.
• Exile Shifting Tides of Mana: You gain 15 life. You may draw two cards.