He mentions the D&D dice in the vid, and actually, that was my first thought as well. :^) The Romans had a game similar to our “Risk”.
He did say the heavy side would land down but that’s not 100% true, land that way more often but not always. And maybe it was like craps, most common roll is a loser. And really there’s so many things you could do. Put stuff inside, shake it around and see where it falls out. Maybe put a bunch of sticks in the ground and get points for landing it around a stick. The lack of instructions pretty much guarantees it was entertainment. Maybe one guy started making them and that area had a little fad.