There was this request thread the other day that I saw about this anime themed world where people claimed spheres of magic based on the major arcana of the tarot. I thought this was a fabulous base idea, but since I'm not a fan of established settings, I thought I might see what sort of game could naturally come of it.
There are infinite ways that such a thing could be instituted into a game, but they break down into distinct categories. Which of these would be the most fun to play? In addition, what time period or alternate universe would be most fun to play it in?