Fun little dice roller, not quite sure where the "opposite" comes in other than mentioning something at the beginning, but still a nice little gaff!
Dice were interesting, may have to steal that design for an in house D&D game xD
Dave here. You're more than welcome to pinch them.
I've popped the STL files in a quick repo in case you did want to print them off :)
https://github.com/dmckrogers/dotun