The Day of the Doctor

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Exile cards from the top of your library until you exile a legendary card. You may play that card for as long as this Saga remains on the battlefield. Put the rest of those exiled cards on the bottom of your library in a random order.
IV — Choose up to three Doctors. You may exile all other creatures. If you do, this Saga deals 13 damage to you.