Endemic Plague | Magic: The Gathering
Formats Endemic Plague is Legal in
Official Oracle Text for Endemic Plague
Destroy all creatures that share a creature type with the sacrificed creature. They can't be regenerated.
Official Rulings for Endemic Plague
4/15/2013 : Players can only respond once this spell has been cast and all its costs have been paid. No one can try to destroy the creature you sacrificed to prevent you from casting this spell.