NEX  

Copyright (c) 2004 João Pedro Neto

Nex is played in the same board as Hex:

The game needs also a set of neutral pieces that are shared by both players.

TURN - On each turn, each player either: drops one friendly stone and one neutral stone in empty cells replace two neutral stones by friendly stones, and another friendly stone by a neutral stone GOAL - The first player (say, Black) is to form a unbroken chain of stones that connects the SE and  NW sides of the board, while the second player (say, White) attempts to form an unbroken chain of her stones connecting the SW and NE sides of the board.

 

An example In this position, Black resigns. There are a triple threat of connection at the marked neutral stones. Even if Black replaces two of them, White still has the third to make a winning connection.

The use of neutral stones greatly increases the game complexity with a small increase in rule complexity. The tactical possibilities are larger since neutral stones are both a benefit and a problem shared by both players.

Whatever the options of White and Black, the number of black and white stones will always be equal at the end of each turn. The number of neutral stones, however, can change and be reduced even to zero.

Nex games are full of tactical subtleties. An interesting feature is that there are no useless stones on board; it is always possible to recycle them to swap a pair of neutral stones.

When the number of neutral stones rises, the game reaches a critical mass that produces swap battles that may decide the winner. Forcing moves (i.e., making the adversary to play at a specific point) are the easiest way of preventing the adversary from swapping important neutral stones on his next turn.

It is common the co-existence of two plans: one with friendly pieces and another based on neutral structures that mines the adversary groups and may provide an alternative path to victory.

In the extreme (and rare) case where the board is almost full, we apply the following conventions:

• When there is only one empty hexagon and there are no neutral stones, the player just drops a friendly stone.
• When there is only one neutral stone and no empty hexagons, the player converts the remaining neutral into a friendly stone.
• When there is one neutral and one empty hexagon, the player drops a friendly stone on the empty hexagon and the opponent converts the neutral stone.

After each one of this moves, the game will surely end.

These conventions are required to completely define Nex and any other game where this mutator is applied. Actually, games like Gomoku, Y and Gonnect can be transformed into very nice variants with this concept.