"An alien culture with more than one aspect is against Paramount's guidelines, so Betazoid Chess is exactly like standard chess except that all the pieces represent emotional states. The moves you can make are based on the states."
"I believe I will understand better if I play."
* * *
"Wait. I thought that the Angry piece could only go two squares."
"Emotional states are changeable, of course. Now the Angry piece is Happy, so it can go three squares."
"I see. This game is not equivalent to chess at all, but to the ancient Earth game known as Calvinball."