The rules

Everything you need to play a full game, in order.

The goal

End the game with the lowest score. Points are a penalty, not a prize. Every die you bank adds points equal to how far it landed from its maximum face, so your whole job is to lock in high rolls and avoid burying yourself with low ones.

The dice

A game uses fifteen dice in total:

Twelve six-sided dice. One of them is a special "Bitches" die in the physical set; in this version it scores the same as a normal six-sided die.
One eight-sided die (max value 8).
One ten-sided die (max value 10).
One twelve-sided die (max value 12).

The bigger dice are the dangerous ones, because a low roll on a twelve-sided die can cost far more than any six-sided die ever could.

Taking a turn

Roll everything. Throw all fifteen dice at once.
Set at least one aside. Pick one or more dice to bank for good. You must bank at least one die every roll, and you can bank as many as you like.
Reroll the rest. Throw the dice you did not bank.
Repeat until every die has been set aside.

Because you have to bank at least one die per roll, you can never just keep rerolling forever waiting for perfect numbers. Sooner or later a bad die has to go into your pile.

Scoring

Each banked die scores its maximum value minus the number it shows:

A six-sided die showing 6 scores 0. Showing 4 scores 2 (6 minus 4).
An eight-sided die showing 8 scores 0. Showing 5 scores 3 (8 minus 5).
A twelve-sided die showing 12 scores 0. Showing 1 scores a brutal 11 (12 minus 1).

Add up the points from all fifteen of your dice. That total is your score for the round. Lowest score wins. A perfect, basically impossible round would be every die landing on its maximum for a score of zero.

A worked turn

You roll all fifteen. Your twelve-sided die comes up 11 and your ten-sided comes up 10. Those are excellent, so you bank both immediately (scoring 1 and 0). You also have a couple of sixes showing on six-sided dice, so you bank those too for 0 each.

You reroll the rest. This time nothing big is left, but an eight-sided die shows 8, so you bank it for 0 and a few mid sixes. You keep going. On your last reroll you are stuck with two low six-sided dice showing 2 and 3, and the rule forces you to bank them, costing 4 and 3. Your final pile adds up to your score for the round.

Winning

In a single round, the lowest total wins. For a longer night, play several rounds and add up the scores, with the lowest grand total taking it. Ties share the win, or play one more round to break them.

Now that you know the rules, the real skill is in when to bank. The strategy guide walks through it. Or just jump into a game.