Myrah, Duchess of Never-Was

You may cast exiled cards you own without paying their mana costs by exiling a spell you control with the same mana cost.
"There was a never queen, who ruled a never land. She wore a never-silken glove upon a never-iron hand. She spoke in tones of thunder: "From my will you shall not stray. And if you dare to try it, then you'll rue the never day!"