It seems real strong, but only time will tell if the deck is a flash in the pan, or if it has the staying power to succeed alongside current top-tier strategies like Affinity and Eldrazi Tron
You can then deal four damage to any creature or planeswalker you want, which is great for finishing off any lingering creatures or planeswalkers after combat
Sacrifice another creature: Untap this and put a +1/+1 counter on this
Khans allows you to exile the top card of your library and play it until the end of your turn, while Dragons allows you to deal one damage to any target when one of your creatures leaves the battlefield
That didn't feel quite as black as it could and tying the two events together really helps sell the whole massive-change-to-your-essence thing I was going for
You can get similar one hit mill effects on much cheaper cards and not being able to rely on Jace's 2nd hit while at the same time needing to ensure you have around 4 big hits in your deck total, you might as well just run the cheaper cards