It's less powerful but in a singleton format like Commander, anything remotely close to Necropotence would be a strong card draw engine in Black
Granted, it's tapped Treasure, and it's gated to once per turn, but that's only fair given you can convert your stash of Treasure tokens into 4/4 fliers with haste
Protection from everything is rare text in Magic , as it leads to noninteractive games
On top of that, when you sacrifice it, you get tempted by the ring, making it an auto addition to decks that care about the mechanic, or just to at least make something harder to block
They eat fewer creatures while blocking and often cant stop opposing three mana creatures
At the end of this war, Urza discovered the dark plane of Phyrexia, a hell of flesh, metal, and grease, where the line between living and artificial was blurred