Mystic Forge

If the top card of your library has a morph ability, you can cast it face down from the top of your library, even if it's normally not a colorless card.

If the top card of your library changes while you're casting a spell, playing a land, or activating an ability, you can't look at the new top card until you finish doing so. This means that if you cast the top card of your library, you can't look at the next one until you're done paying for that spell.

You must follow the normal timing permissions and restrictions of the spells you cast from your library.