Four thousand years after Urza and Mishra reopened the portal to Phyrexia, the evil lord Yawgmoth sits poised to invade his one-time home-Dominaria. The plane's only hope for survival is a cache of powerful artifacts known collectively as the Legacy. When put together to assemble a powerful dooms-day weapon, these artifacts will have the potential to destroy the dark powers that will try to invade the planet. The focal point of this weapon is a flying ship called Weatherlight, and its intrepid crew searches the planes to find all of the pieces of the Legacy before the invasion commences.