My FLGS was using a shoe box lid as a dice tray. I knew what needed to be done. I started with just a large 200x200 dice box, decided why not add a lid to keep dice or to use it as terrain, then of course I had to add a tower that could fit inside while storing it.
The inspiration for the design came user Terrain4Print
There are 50 dice in each of the pictures for reference.
The top with the grid is 28mm squares.
Extrudr PLA NX2
Print the tray normally.
Print the top upside down.
Print the tower on its side.