This cube started out as an alternative to doing a bad rare draft, since it was tough to get enough people to each contribute 45 rares. Then, it turned into its own thing, and has been a lot of fun to draft.
The main rule is that all cards have to be rare or mythic, and can't be worth more that $1. A few exceptions have been made, such as Dromar, since I wanted to include that full cycle of dragons. I've also been very lax on this rule when it comes to the lands. I won't include the higher end lands, like Dual lands or Shock lands, but have included lands like Hinterland Harbor to make the mana bases work better.