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Magic: The Gathering Comprehensive Rules Changes

Masters Edition to Lorwyn (Single Change View)

General changes

Old rule (Masters Edition) New rule (Lorwyn)

309.5.

If a creature is put into play blocking, its controller chooses which attacking creature it's blocking as it comes into play (unless the effect that put it into play specifies what it's blocking). Such creatures are "blocking" but, for the purposes of trigger events and effects, they never "blocked."