[This description is outdated. Will update when I have the time.]
Glory to the revolution! The Khans have been overthrown, the Dragons are a worry of the forgotten past - this is the age of the common card! And indeed, all cards shall be common, though some cards more common than others.
This is a Peasant (common and uncommon cards only) set cube of Khans of Tarkir. There are between one, two, and three copies of every common in the set (plus five from Fate Reforged and five from Dragons of Tarkir), and exactly one copy of every uncommon in the set (plus eleven from Fate Reforged and five from Dragons of Tarkir).
This cube is intended to create a draft environment that requires a constant reading of signals and a healthy knowledge of how Khans is supposed to be drafted. One of each uncommon limits each of the deck archetypes to one or two people, and ensures they'll need mediocre or even bad cards to fill out a deck, rather than getting randomly lucky in regards to pre-draft setup. Most commons are 3-of; some of the bad commons (plus Woolly Loxodon, because nobody wants to play against a deck with three Woolly Loxodons) are 2-of; and there's only one Lens of Clarity, because I refused to cut any card entirely and wanted to give people the option to meme if they were willing to sacrifice for it.
The cards from outside of KTK are still within the Tarkir block for flavor and balancing reasons:
According to Marshall Sutcliffe and LSV, arguably two of the most trustworthy authorities on Limited, Khans of Tarkir draft (KTK, KTK, KTK) is one of the best draft environments in history. Their Sunset Show on the set (Limited Resources 266) is my suggestion if you'd like to hear their explanation for why.
Since this is a 360-card cube, all cards should be drafted in an eight-player pod. My suggested 15-card pack structure regardless of number of drafters would be four random uncommons and eleven random commons.