This dice tower doesn't require any supports and can be printed in a single piece.
75% scale is enough for most dices, although you can experience some issues with d20.
85% is enough for all dice sets
If you want to modify something, you can find SCAD sources here: https://github.com/hirthwork/dice-tower.scad
Please, keep in mind that this dice tower requires a lot of filament. 85% scale model with 10% infill requires 330g of ABS plastic without skirt and brim. It will be quite frustrating to found that you out of plastic after 48 hours of printing
At first I tried to print https://www.thingiverse.com/thing:3127957 but found that supports are not so easy to remove. And this thing have a lot of them: under the stair steps roundings, under the knight figure postament, for the spiral strairs, they are all hard to remove.
So my challenge was to create spiral stairs tower which doesn't require supports at all.
Each stair rests on top of arc-shaped base, which relies either on floor or walls.
Another challenge was to create rocks around the tower and dice area. I found that rocks similar to nature created ones can be produced by intersection of several random-sized cubes which are rotated by random angle around all three axis.