The Coming of Galactus

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I — Destroy up to one target nonland permanent.
II, III — Each opponent loses 2 life.
IV — Create Galactus, a legendary 16/16 black Elder Alien creature token with flying, trample, and "Whenever Galactus attacks, destroy target land."