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Magic: The Gathering Comprehensive Rules Changes

Eventide to Shards of Alara (Single Change View)

General changes

Old rule (Eventide) New rule (Shards of Alara)

421.6.

If the loop contains an effect that says "[X] unless [Y]," where [X] and [Y] are each actions, no player can be forced to perform [Y] to break the loop. If no player chooses to perform [Y], the loop will continue as though [X] were mandatory.