Knight of the Reliquary plus Retreat to Coralhelm isn't new technology. Neither is using Nahiri, the Harbinger to find Emrakul, the Aeons Torn. Knight and Nahiri are both relatively resilient threats, and Eli Kassis' use of their juxtaposition to win the Modern Classic in Worcester is pretty cool stuff:

I really like that this build of the deck gets to trim down to 2 Retreats given the access to more win conditions. This lowers the ability of the deck to combo off on turn three, but it makes the deck more resilient in longer games and gives it on average better top decks.

Mostly, this deck just plays ABC Magic with relatively boring creatures with its only ways to really present a gameplan that is powerful relative to Modern being its two combos. With that being the case, I can't say that I would recommend this deck over Kiki Chord, as the value provided in that deck will generally be more consistent and more difficult to play around.

The one of Zealous Conscripts has gained a lot of stock with the printing of Nahiri- especially when you have Emrakul in your deck. That said, this particular deck is less equipped to take advantage of it than a deck with Chord of Calling. Eli has been doing well with Retreat combo in Modern lately, though I wouldn't advise that others pick up this deck, even if elements of it are very impressive.