Which cards have the power to break into a Standard format defined by the speed and resilience of Izzet Prowess, the overwhelming card advantage and inevitability of Zur Overlords, and the limit-testing nature of the formats premier combo deck, Azorius Omniscience
Once Sahagin has been blocked, casting a noncreature spell in order to cause Sahagin's ability to trigger won't cause Sahagin to become unblocked
Standard Procedure becomes that card until end of turn
Other times, as with Daru Stinger above, it meant giving the creature an ability that cared how many +1/+1 counters were on the creature
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