Octagon is ideally played with a 40-card deck containing six suits; the cards are numbered 1-12 but the suits have different numbers of cards, e.g. the blue suit consists of 1, 6, 7, and 12. Most of the cards are shuffled and dealt into eight face-down piles of four cards each, in the form of an octagon. The blue cards and matching black cards are placed face-up on top of these as the dealer chooses. A turn consists of picking up a stack of cards, revealing them, and then placing them on successive stacks in clockwise order. If a stack has just one or two cards in it the top card can be captured by placing a card of the same rank on it. There are a few additional rules, e.g. when capturing counterclockwise moves may be made. At the end of the round captured cards are scored; different suits score differently, e.g. the blue cards are 10 points each, black cards (the longest suit) score only for the player with the most, red cards score for sequences, etc. Four players play in partnerships; while the rules technically allow for play by four or five individuals, only three play at a time. Rules are provided to allow play with a standard deck.