Though having your opponents creatures to swing out with is good, just having it locked down under your control can also be a big win.
Remember, Im aiming for cards that put an opponents life to 0 or straight up cause them to lose the game
Stensian Sanguinist // Exsanguinate would fit best in a monoblack or Rakdos (blackred) Commander deck built around lifedrain, combat pressure, and spell recursion, especially one that can reliably attack and connect to enable the prepared mechanic so you can repeatedly copy a scalable finisher
it was first changed to "unaffected by summoning sickness" in Mirage and then replaced with the keyword Haste in Urza's Destiny
Its an amazing win condition, and its the kind of thing that fits perfectly with the inherent thievery that exists in the rogues youll be playing with
Sacrifice outlets and repeatable egg-makers turn Atla into a reliable engine that overwhelms opponents with must-answer creatures