• Everyone gets three cards face down, three face up on top of those, and three in hand. Before play you can swap hand cards with your face up cards, so put your best on show.
• The lowest card starts. Play a card equal to or higher than the one on top, then draw back up to three. Cannot play? Pick up the whole pile.
• 2 plays on anything and resets the pile. 10 plays on anything, burns the pile and you go again. Four of a kind in a row burns it too.
• 7 means the next card must be a 7 or lower (you can switch this off in the lobby).
• When the stock runs out, play your hand, then your face up cards, then your face down cards blind, one at a time. A blind card that does not fit means picking up the pile.
• You cannot go out on a 2 or a 10 (also a lobby switch). Last player holding cards is the Shithead.

Before anyone joins in, the server locks in a secret and shows you its SHA-256 fingerprint. Then your own device adds a random number of its own. The shuffle comes only from those two, so the server cannot pick the deal and neither can you. When the game ends the secret is revealed, and your browser re-runs the shuffle and checks every card. Every game gets a fresh secret, and you can download the whole proof.