|Pyramid power||Suit||Card power|
Unless specified otherwise (e.g., the upright cases), your pyramid must be pointing directly at an adjacent pyramid or space to affect it.
Dectana is a game for 2–5 players; it requires a double Decktet (with or without the extended deck cards), plus one color of Looney Pyramids per player (specifically, 3 small, 3 medium and 3 large pyramids in that color; if substituting some other object for them, note that pyramids have one, two, or three pips on them, are pointy, and can be stood upright).
To begin, shuffle the double deck and lay out 9 cards in a square, 3x3 pattern, alternating orientation horizontally and vertically. Deal three cards to each player. Choose a start player.
Scores are determined by adding up the value of all cards occupied solely by the player; the highest score wins. (The tiebreaker is number of pyramids on the board.)
A space is any place on the board where cards and pyramids may be placed. Spaces are adjacent if they share an orthogonal side with each other. Spaces are never adjacent diagonally.
A territory is a space that contains at least one card. If there are multiple cards there, only the top card is considered. If the top card is removed, then the topmost remaining card is considered instead. As a rule, you cannot do anything to a territory's card if there are any pyramids on it.
A wasteland space is a space that is not a territory, but is adjacent to one.
The void is any space beyond the wasteland, a space that is adjacent only to wasteland spaces. Pyramids and cards cannot be played here, and any pyramid in the void is immediately destroyed.
When a pyramid is destroyed, it is returned to the player for reuse.
A piece on the board may point in any of the four cardinal directions or point straight up. To orient a piece is to change its direction to any of the five legal directions.
A flat pyramid lies on its side. It can point in any of the four cardinal directions. It is pointing at the nearest adjacent space in that direction, whether wasteland or territory. It never points at a space two or more steps away.
An upright pyramid stands on its base. It is pointing at nothing in particular.
Crowns allow you to use their suit three time.
Ranked cards are worth their rank, Aces are worth 1, and all other cards (Crowns, Pawns, and Courts) are worth zero, while Excuses are worth an even lower value of zero.
After your action, discard down to the hand limit (6 cards).
The game ends at any time after the deck has been run through (and discards shuffled), when a player discards three Aces from their hand.