We bought Planechase over the weekend. We used the planar deck with my Cube, and it was super fun and crazy.
I was playtesting my rebuilt Make or Break Cube, so in some ways the planar cards worked well, adding in even more chaos. But it was difficult to tell how well the Cube was working on its own!
The planes sometimes benefit one player, sometimes none, sometimes all. Planar cards are popular in Commander; I think it’d be fun to use with Conspiracy — not only would there be the usual deals, but then add in the “please don’t roll the die and change the plane” element…..So much fun. And possible hatred. 🙂