mtg commander vampire deck Black/White - Custom Built 100-Card EDH Deck The Gathering Crimson Vow Commander Upgrade Guide:

Paying just 1 extra mana gives you a copy of that spell, which can swing the game fast

I think this works in Up the Beanstalk decks in Standard, maybe Pia Nalaar, Consul of Revival decks, but probably in no other context in 60-card formats

Exerted characters cant quest, challenge, sing, or use abilities that require them to be exerted

Blinking the cloaked creature will return it face up

And sure, this can grant indestructibility when it enters, or can do it at instant speed if you have the mana for disguise which means that it will kill whatever blocks it and survive thanks to death touch and indestructibility, but it seems like youre just paying too much mana for this no matter how you deploy it