Each player sacrifices five lands. Destructive Force deals 5 damage to each creature.
The end of the world rarely comes quietly.
Official Rulings for Destructive Force
8/15/2010 : First the player whose turn it is chooses five lands to sacrifice, then each other player in turn order does the same, then all chosen lands are sacrificed at the same time. After that, Destructive Force deals 5 damage to each creature.
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