Ragnarök, Worlds end

You cant spend mana to cast this spell
{p/w}{p/w}{p/u}{p/u}{p/r}{p/r}{p/g}{p/g}{p/b}{p/b}: Each player discards their hand, and sacrifices all permanents, then exile each permanent sacrificed this way.
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The end of the world was prophesied, and sadly, unstoppable.