Using discs that may or may not touch each other introduces problems that require a software judge to decide if discs touch or not (I'm referring to Go on a board without lines)
This variant attempts to reduce Go to a most primitive form, which could be played e.g. on a beach with pebbles, shells, etc...
- 'stones' are two-dimensional extruded metal shapes with significant thickness (e.g. 5 mm)
- The playing surface is magnetic (to keep stones from shifting), of possibly irregular shape
- players are electrically wired so that if they touch the playing surface, their move is invalid, or equal to suicide (to decide). the idea is to drop stones onto the surface, without disturbing it.
- two stones are connected if the attacking player can play a move that touches the two stones.
- a group is dead if the owning player cannot add (drop) a stone to it
- stone counting is in effect
- to decide what stones belong to a group, the player at move must be able to drop a shape that can connect each pair of successive stones that belongs to the same group
- goban shape is irrelevant but can be decided or fixed by convention
- playing shapes ('stones') can be regularly shaped (eg discs) or not, can be identical or not (eg in case this gets programmed, generated randomly such as in Tetrix).
- Why two-dimensional *extruded* shapes ? The idea is that a player should drop the shape in place (i.e. without touching the surface and disturbing existing shapes). As a result, either the shape will completely stick to the playing surface, or part of it will be elevated by a shape that is already on the goban. In which case the move is rejected or considered suicide. The significant thickness ensures that a shape can only stick completely to the surface, or it will stick out.
- the 'dead group' rule is also applicable to dropped shapes: if they didn't kill a group, but the player cannot add a shape, they are dead and thus removed (=suicide rule)