Dargoth's Will

Each opponent exiles the top two cards of their
library. You may play cards for as long as they
remain exiled, and you may spend mana as
though it were mana of any color to cast those
spells.
"When the Hour of Devastation commenced, many resisted the God-Pharaoh's embrace. I have no
sympathy for those who did."
— Dargoth, Disciple of Bolas