Combat is divided into four turn sequences: Player Declares Attack
As I mentioned earlier, there are a number of cards that can use the exiled cards as fodder for various effects in addition to just milling folks
Our last attempt at a scrying-matters card didnt work out too well (The Temporal Anchor), but Planetarium of Wan Shi Tong has much higher upside: It lets you cast spells for free rather than just stockpile extra cards
There are also some creatures that interact with the graveyard, such as Scavenging Ooze, Anafenza the Foremost, and Remorseful Cleric
Whether Ravnica at War should see play depends on the specific metagame and the prevalence of multicolored permanents in the opponent's decks
Force of Negation remains a major player years after its introduction, though whether it has done a better job at stymieing degenerate strategies or enabling them is a hot topic of debate