Twirls of Action

Copyright (c) 2001 Claude Chaunier and Joćo Pedro Neto

Claude had an idea of a pivot moving after seeing SCALUS pivot scaling concept. After some discussions with the abstract games community, we designed a game based on what Claude named by Twirls. A Twirl is a kind of cooperative move. An isolated stone is not able move, it always needs the 'help' of another one, in order to move through the abstract board where the game flows. Of course, the game was also inspired by the Lines of Action abstract game, and that reflects on the game's name! 

TWIRLS OF ACTION is played on a 9x9 or 8x8 Go board. The initial setups follow:


TURNS - Black starts playing. Players may not pass.
PIE RULE - After Black's first move, White may swap sides.
MOVE - Each stone move by a Twirl movement. This is done on the following steps:
Select an enemy stone as the Pivot (at a distance of N cells);
The Pivot must be on a straight line (diagonal or orthogonal) without any other stone in-between;
The stone can go another empty cell at the distance of N cells from the Pivot;
The origin and the destiny cell must be on a straight line (diagonal or orthogonal) without any other stone in-between;
GOAL - Wins the player that connects all of his stones, where each stone does not have more than 3 adjacent (diagonal or orthogonal) friendly stones.

A valid Twirl may have stones between the pivot and the destiny cell. This implies that Twirl move may be irreversible! As Claude says, this makes move orders important, makes the board more like a puzzle than a gas, makes the game more like an adventure than a clean equation, and gives us more ideas to plan with a sharper responsibility. 
The connection restriction was defined to create a harder winning goal for both players. Otherwise, the game is too fast and easy for the 1st player. 
For a harder game, people may like to restrict it to a maximum of 2 adjacent stones
This also can be altered to define handicaps. A weaker player can win by creating chains with 4 neighbors, and the stronger player must create chains with at most 2 neighbors!.

Some basic Twirls

Stone D8 moved to D5 using A5 as a Pivot. Then White moved his A6 stone using C8 as a Pivot.

Now, Stone C8 can go to C4 using E6. The D5 stone does not interfere, since there are no restrictions on the path between the Pivot and the destiny cell (check the Twirl definition).


Winning Restrictions...

White does not won yet! Despite the fact that all White stones are connected, stone F4 is adjacent to 5 friendly stones.