This cube is built entirely from the nine major sets from the plane of Ravnica: Ravnica, Guildpact, Dissension, Return to Ravnica, Gatecrash, Dragon's Maze, Guilds of Ravnica, Ravnica Allegiance, and War of the Spark.
The cube is 650 cards, but it is designed to be drafted at 450 cards, supporting a maximum of ten players. There is a core section of 250 monocolor and colorless cards that are included in every draft, which are supplemented by selecting a set of five guild sections, each of which contains 40 cards. The guild sections contain cards within the guild's colors, as well as monocolor cards that contain the guild's watermark, and lands supporting those guild's colors. Guilds are added such that each color is represented twice; there are 12 possible five-guild combinations that satisfy this requirement.
Varying but limiting the guilds in this way produces a more Ravnica-feeling experience than mixing in all ten guilds at once; each deck tends to gravitate around one guild rather than mixing guilds into a three-color pile, and sometimes a player attempts a five-color Gates deck as well. The variance of the different guild combinations makes each draft a unique and enjoyable experience.