Prioritize Zombie synergies like lords, repeatable token makers, and death triggers
Smothering Tithe demands twice as much tax each time an opponent draws a card, and the steady buildup of mana can get out of hand in a hurry, especially in conjunction with all draw effects like Magus of the Wheel
Elenda and Azor is no slouch either, so this deck should operate fine with either commander at the head
It's possible that, as brackets continue to increase in adoption, maybe this would be an acceptable Game Changer, though, even then, Upgraded decks don't want mass land denial around
If a creature affected by the first triggered ability of Impetuous Devils is tapped or is affected by a spell or ability that says it cant block, then it doesnt block
I suspect, however, that there are going to be plenty of cases when you have much scarier things to block