Sacrificing a Clue to draw a card is great
This certainly slows things down for Savvy Trader a bit, but as discussed in this article, the card has definitely found its home in the Commander format.
Outside of Commander, you see the Planeswalker in dedicated Mono-Black Standard lists alongside Lolth, Spider Queen
This five drop 5/5 on curve Naya colored dork gets bigger as more Auras are added in size, and that's card disadvantage if you kill it, but not without jumping through some targeted restrictions first, and you can Edict them, but they'll sac another dork, or Damnation the board, but respond with Heroic Intervention or just give it an indestructible Aura
Ive even convinced a friend to stop running Sign In Blood after killing him with it
This depends entirely on what cards you have, if theyre on the reserved list, and many more factors