Copyright (c) 2000 W. D. Troyka
Breakthrough is a two player game played on a NxN square board. These are the three configurations proposed by W. Troyka.
Some playing tips are given by the author: This diagonal motion allows you to 'skirt' by an opponent piece by facing it head on, where it cannot capture you, and then moving diagonally around it. As a result, a single piece cannot by itself prevent an opponent piece from 'breaking through' the ranks. When pieces are spaced out along diagonals, an opponent piece can easily skirt through them. Look for weak links in your opponent's defenses where a single piece to the rear is guarding two attack routes.
There is a ZRF to play Breakthrough with Zillions. Just a side note: I left the Zillions engine compute for some time the 5x5 setup. After more than 130 million positions analyzed, it could not give me a solution for the game!
Black can win in 3 moves. Can you find it?
Solution: b3-b2! c1:b2 c3:b2 and win in one move
Breakthrough was the winner of the first 8x8 Game Design Competition, held in 2000/1. More details can be found on Abstract Games Magazine 7. A hexagonal variant from the same author is Sidewinder where stones may slide forward any number of empty cells.