Overview

Attangle is a two-player abstract strategy game played on a hexagonal board. Players place and capture pieces to build stacks. The first player to create 3 triple stacks (stacks of 3 pieces) of their own color wins the game. It is part of the Stacking Game Trilogy by Dieter Stein, along with Accasta and Abande.

Components

• 1 Hexagonal game board (4 spaces per side, 37 intersections)
• 36 Playing pieces (18 black, 18 white), stackable

Setup

1. Place the empty board between the two players.
2. Each player chooses a color (black or white) and takes their 18 pieces, placing them in a visible pool in front of them.
3. The board starts completely empty.
4. White plays first.

Turn Structure

Players alternate turns. A player must take a turn on every turn; passing is not allowed. On each turn, the player performs exactly one of two actions: Place or Capture.

Actions

Place a Piece

Take a piece from your pool and place it on any vacant intersection on the board, except the center (d4), which must remain empty throughout the entire game.

Capture an Opposing Piece or Stack

To capture, a player moves exactly 2 of their own pieces/stacks from two different directions so that both converge on a single opposing piece or double stack. The two moving pieces/stacks must form an angle (intersect) at the target location.

Capture rules:

• Each piece or stack moves in a straight line along one of the 6 directions on the hex grid.
• Pieces/stacks may move across the center intersection.
• Pieces/stacks may not jump over any other pieces or stacks (friendly or opposing).
• Pieces/stacks can only be moved as part of a capture; they cannot move to empty spaces or onto friendly pieces/stacks.
• The two capturing pieces must move simultaneously from different directions.
• After the capture, the 2 topmost pieces of the resulting stack must belong to the current player.

After a capture:

• The current player takes back the topmost piece of the newly created stack and returns it to their pool.
• No stack may exceed 3 pieces in height after this retrieval step.
• Once formed, stacks may never be split.

Mandatory capture: If a player has no pieces left in their pool, they must capture on their turn.

Scoring / Victory Conditions

The first player to create their third triple stack (a stack of exactly 3 pieces) wins the game immediately. Triple stacks are permanent: they can never be captured or moved for the rest of the game and remain on the board.

Special Rules & Edge Cases

• The center intersection (d4) must remain vacant for the entire game. No piece may be placed there, though pieces may move across it during captures.
• Stacks can only be 2 or 3 pieces high.
• Triple stacks (3 pieces) are frozen on the board permanently; they cannot be captured or moved.
• A capture can involve any combination of single pieces and double stacks (two singles, or one single plus one double stack).
• If a player cannot place (pool is empty) and cannot capture, the game is a draw (though this is extremely rare in practice).

Player Reference

Action	Requirement
Place	Take 1 piece from pool, place on any vacant intersection except center
Capture	Move exactly 2 friendly pieces/stacks from different directions onto 1 enemy piece/stack

Win condition: First to create 3 triple stacks.

Key restrictions:

• Center (d4) always empty
• No jumping
• Max stack height: 3
• After capture, return top piece to pool
• Triple stacks are permanent and immovable