Simon Bradshaw

In a friends-locked post of mine purplecthulhu commented on a report about a US court ordering the parties to resolve a trivial dispute via Rock-Paper-Scissors by suggesting that the variant with Lizard and Spock be used. I responded by suggesting that the higher the court the more complex the game should be, and proposed Rock-Paper-Scissors-Lizard-Spock-Starfish-Unicorn-Shotglass-Segway for the Supreme Court.

Now cuboid_ursinoid wants that as a T-Shirt. So I suppose we need some rules.

It turns out that N-option generalised Rock-Paper-Scissors works so long as:

- There is an odd number of options.
- Each options beats exactly half the other options and is beaten by the other half of them.

So, trivially, in classic RPS, Rock is beaten (wrapped) by paper and beats (breaks) scissors, and so on. RPS-5 adds two new options:

Spock vaporises Rock and breaks Scissors but is poisoned by Lizard and disproven by Paper.
Lizard eats Paper and poisons Spock but is crushed by Rock and decapitated by Scissors.

Thus RPS-5 has another 7 interactions (we've just listed Spock/Lizard twice) to add to the three in classic RPS for a total of 10.

We thus need more interactions. Indeed, since for RPS-N, there are N(N-1)/2 interactions, for RPS-9 we need 36 interactions of which we already know 10, so we need 26 more! Remember, each new option must defeat half the others and be defeated by the other half of them.

I can think of a few:

Spock rides Segway
Spock dissects Starfish
Shotglass inebriates Spock
Unicorn impales Spock
Rock trips Segway
Starfish grips Rock
Rock smashes Shotglass
Unicorn kicks Rock

...but we need more. So, fire away!