Wedded in Shadows

Whenever you draw a card, target opponent exiles the top three cards of their library. You may cast one of those cards this turn, and you may spend mana as though it were mana of any color to cast it.

Fateful Unity- As long as Wedded in Shadows, are on the battlefield, spells you cast from exile cost {1} less to cast.
{2}{u}{b} Return Wedded in Shadows to their owner's hand.

"In life, they vowed to protect each other. In death, they vowed to protect the world."