Resources

Magic: The Gathering Comprehensive Rules Changes

Planar Chaos to Future Sight (Single Change View)

General changes

Old rule (Planar Chaos) New rule (Future Sight)

Poisonous

Poisonous is a triggered ability. "Poisonous N" means "Whenever this creature deals combat damage to a player, that player gets N poison counters." See rule 502.69, "Poisonous."