Theres a lot of potential here if you can pose somewhat ambiguously, but its not going to be as useful if you dont have some dedicated followers
(It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything controlled by those players.) Fateful hour If you have 5 or less life, you can't lose life this turn, you can't lose the game this turn, and your opponents can't win the game this turn
This is so effective because your opponent cant target the hexproof creatures themselves, which means you can safely put as mana auras on them as you want
If you're willing to splash into black, I think Tear Asunder is better than Shattering Blow while having the option to kick and remove creatures and planeswalkers in a pinch
I dont play enough of the format to know how good this is in cEDH, but its a fine way to protect a combo in casual pods
Hour of Revelation In the same vein as Vanquish the Horde, Hour of Revelation gets cheaper when you want it, and is only really six mana before the board has hit critical mass