When Unwilling Vessel dies, create an X/X blue Spirit creature token with flying, where X is the number of counters on Unwilling Vessel
For certain Commander players, immersion-breaking power isn't worth it, even if these decks can win them many games with the overwhelming power of artifacts, +1/+1 counters, and living semi trucks that roll out and attack for lethal.
Knowing that's an option, I get a lot of requests for another -1/-1 counter block
Gaining Hexproof is also super-relevant, as it turns off direct damage effects, discard effects, and a lot of graveyard hate all in one swoop
On average it is the second best removal spell in all of magic and there is a fair old gap between 2nd and 3rd
Alrund's Epiphany also has foretell, which is a mechanic that allows you to pay two mana to put it into exile and makes it cost only six mana in a later turn