This cube has a single, central mission: to be f-UN.
This single, individual mission has three parts. Individually. Together.
Firstly, each card should be in the 'UN' magic spirit. The card does not specifically have to be silver bordered (which is especially true in light of WOTC's announcement regarding cards being black bordered in Unfinity, see https://magic.wizards.com/en/articles/archive/making-magic/unfinity-and-beyond-2021-11-29). Rather, it should embody a somewhat whimsical and chaotic feeling that bends but does not break the rules and conventions of Magic. Okay, maybe some cards may bend the rules into a pretzel, but its a pretzel, who doesn't love pretzels?!? (Not the crunchy kind the like soft baked kind).
Thirdly, each card should embody the spirit of fun. Or, rather, f-UN. Whatever and/or whichever. The card must be f-UN to play with, against, and around -- everybody wants to get to enjoy playing the cards they have drafted and show off the fruit of their drafting and deck construction skillz. Nobody in history has watched their opponent go 'Island, lotus, t3feri, plus, pass' and felt involved or interested in the game. Not hating on any of these cards (well, actually...kinda hating on you t3feri) but they do not reward drafting and deck construction. Lotus is good in...every single deck ever. All this being said, a little bit of salt does enhance the flavor of your dish, but f-UN must be prioritized above all. Except the first two mission parameters. But other than that, f-UN above all.
Lastly, the cube itself and each card within is a very subtle and somewhat spaced out f-U. Literally. Well, figuratively. But literally in a figurative way. The cube is not meant to be taken entirely seriously, as it is a way for friends to come together over a hobby they enjoy and play for some silly, goofy, fun games. The f-U is to remind each player that we need to let go a little bit and just have f-UN.
I hope you can enjoy as much as my friends and I have over the years -- Happy quebing!