If you're unfamiliar with the archetype, it's a creatureless control deck built around the long-term card advantage potential of Starfield of Nyx. There are plenty of great enchantments in Standard, especially in the removal department, which is critical for a deck like this to function properly. Silkwrap and Stasis Snare are the standbys, while Oath of Liliana is a great addition now that Nissa, Voice of Zendikar and Gideon, Ally of Zendikar aren't roaming everywhere.
Oath of Jace is the primary card advantage in the list, as the discarded cards can be easily brought back by Starfield of Nyx. But the truly exciting addition to our ever-expanding repertoire of enchantments is Lunar Force.
Lunar Force may not look like much, since it has no immediate impact and your opponent gets to decide which spell to throw away to it, but it plays a key role in this deck. When you have enough cheap removal to keep the battlefield clear, it can ensure your opponent has a difficult time recovering. Also, once you have Starfield of Nyx on the battlefield, you can return Lunar Force each turn while using your other resources to clear up what is left. As your opponent draws lands, eventually they will be locked out of the game.
That means Lunar Force gives this deck a degree of inevitability that it didn't have before. Given how focused it is on small advantages that snowball the longer the game goes, having inevitability is crucial. Decks these days are powerful enough to come back from hopeless spots if given enough time, so you have to build toward something that is game-ending, as opposed to an endless cycle of two-for-ones.
Most of you know me as an aggro player, and for the most part I am. But I do enjoy playing games where my subtle advantages compound over many turns, seeming innocuous when viewed in isolation so as to not alert my opponent that their situation is becoming dire, only to have them realize the gravity of their predicament when it's too late.
That moment when they realize that all is lost but the faintest glimmer of hope that I might blunder the game away is as intoxicating as it is rare. For the most part in Standard, you have to work to end the game quickly, but this deck gives you a sense of comfort that everything will be okay, that there is nothing they can do that you can't handle. That peace of mind would be impossible without Lunar Force, which makes it such an intriguing addition to an already powerful but previously flawed archetype.