There are additional ways to get value off of sacrificing creatures
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General upccc-archive , general-board 41 2257 December 2, 2015 What is something new you have learned in the hobby in 2018
Double the damage the equipped monster inflicts by it's card effect.[/spoiler] [spoiler='Starman'] When a "Mushroom Kingdom Warrior" card is targeted by a card effect: negate the effect and destroy the card targeting the monster.[/spoiler] [spoiler='Poison Flower'] When you would take more than 1500 damage by battle: negate the attack and inflict half the damage you took to your opponents life points.[/spoiler] [spoiler='Poison Mushroom'] When you take 1500 or less damage from battle: inflict damage equal to 2x the damage you took to your opponents life points.[/spoiler] These are all cards that either power up the weak monsters, or prevent them from being destroyed either by battle or by card effects

Yes, Izzet Phoenix is proactive, but outside of the card Ensnaring Bridge, which is difficult for most decks to incorporate, there isnt an effective card to shut down the decks gameplan to the point of neutering it the way that Rest in Peace can against Dredge or Stony Silence can against Affinity