This is a Wilds of Eldraine set cube.
As of right now, it contains 3 of each common, 2 of each uncommon and 1 of each rare/mythic. In the future, I might add one or more full sets of commons and uncommons, so to better represent the math of occurance in a booster draft.
However, the maybeboard contains the uncommons, rares and mythics I have subtracted from the cube. I did this for different reasons: some of them are not good in draft, whereas others are prohibitedly expensive to buy. Some cards overlap these two categories. I have chosen this approach because I wanted to make the most of the booster box I bought, both in terms of giving life to otherwise dead cards in my collection, and continue to gain value from my purchase by drafting the cards more than once.
Interestingly, I found that the booster box contained only a few commons short of three full sets of them, as well as one or two copies of most uncommons. This means that a booster box can be a wonderful way to get started with a set cube as you obtain a large percentage of the cards needed. If you find yourself buying booster boxes anyway, and especially if you enjoyed drafting the set, I recommend converting the leftover contents into a set cube, so you can always bring it out for a night of drafting with friends.
I keep mine unsleeved in a cardboard box for two reasons:
Since I am contend with the fact that these cards are not meant to ever leave the cube or be resold seperately, I don't worry about the condition of the cards more than I would any other toy. The cards will be sleeved after having been drafted and each player's deck built.
I kept all the booster wraps as intact as possible while opening them at first, and now I fill them with similar contents of cards as when I opened them. This also preserves the feeling of drafting new cards.
For lands, I have decided to keep a universal box of random basic lands and sets of sleeves that I bring with whatever set cube we decide to draft (that doesn't have it's own, complete land base). This too preserves the feeling of drafting fresh packs since you don't have full sets of basic lands from the set available then anyway - and once again saves money and space.