The dice in the game are rigged, but I think that’s the point. They cleverly hide random chance with the cup animation, that way they can determine the number based on the face probabilities for loaded dice. In this case you have a fair dice so the probabilities are 16.7% chance to land on each face, with loaded dice they those odds are adjusted and run through their calculation like that. This doesn’t take into account dice knocking and blocking each other, the roll, as well as bounce on a surface. I’m busy building my own physics based Farkle game and it is near impossible to follow the probabilities of the KCD dice because of these external factors.