Journey to Omniscience

You may cast spells from your hand without
paying their mana costs.

Whenever you cast a spell without paying its
mana cost, you may pay {3}{u}{u}. If you don't,
you lose the game.

{7}{u}{u}{u}, Sacrifice Journey to Omniscience:
Search your library for a card named
Omniscience, put it onto the battlefield tapped,
then shuffle your library.