While Magic's history stretches back 30 years, the lore of Dominaria itself is much longer. Returning to a pivotal story of Dominaria's—and Magic's—history, what started as a feud between Urza and Mishra erupted into an all-out war that set into motion the future of the plane and Multiverse itself.

The Brothers' War Collector Booster contains 15 Magic: The Gathering cards and 1 Traditional Foil double-sided token, with a combination of 1 special Mythic Rare, 5 cards of rarity Rare or higher and 4 Uncommon, 4 Common, and 1 Land cards. Every pack contains a total of 10–11 Traditional Foil cards.