mtg exile the top card of your library Urabrask, Heretic Praetor f:commander -c:ubg o:"exile the top"

Her activated ability costs two generic mana and tapping her, allowing a player to sacrifice another creature

If you want to see more brews and builds feel free to check out my profile @ Sargeras

Each option gives a different buff for you and the opponent that had to choose

This card is not going to be the Mill engine, but it happily goes in a typical Dimir Crime deck if you need to pivot away from Mill

The only question that remains is whether or not this set lives up to the promise of offering the best of both the Khans and Dragons versions of Tarkir

Pulling artifacts and colorlessness fully apart would take nearly thirty years