FYI-If I restack my stash of pyramids, I can fit both the treehouse and the reg D6 in the plastic tube. All set for Martian Coasters.
1st Nest-point tip UP
2nd nest=pointy tip DOWN (to fit down next to the 1st)
3rd nest-pointy tip UP (so the base of 3 is flat against the base of 2)
4th nest-pointy tip DOWN (to fit down next to 3)
5th nest- pointy tip up
Now both dice needed for Martian Coasters fits in the tube.