The devotion mechanic has a unique and fun play style that you should play around with if you havent yet
2nd Place: Optimistic Scavenger Behold, the Virtuoso and Priest's newest partner
One of the mechanics showcased in either set, though, did not change
You can Act of Treason that attacking Prossh, Skyraider of Kher, then let Zedruu give it to someone else (removing the end of turn stipulation by superseding it with Zedruus ability)
Marshmist Titan Excluded because it shouldnt ever actually cost you seven
Thalia, Heretic Cathar , on the other hand, just slows your opponents down to a grind because all creatures and nonbasic lands your opponents play have to enter tapped