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The Automaton Wars page

Automaton Wars (previously known as Critical Mass) is a board game for between two and four players, any or all of which can be operated by the computer. Automaton Wars requires RiscOS 2 or later.
Each player has different coloured counters and takes it in turn to place a counter on the board, either on an unoccupied square or on top of a counter of their own colour. When the number of counters on a square exceeds the critical mass for that square, an explosion occurs and one counter is deposited onto each of the adjacent squares - capturing any counters which were previously there.
This may cause those squares in turn to exceed their critical masses, and a chain reaction may ensue. When all of one player's counters have been captured, they are out of the game; the last player left is the winner. There is no such thing as a draw (if the board is connected - exercise, prove this).


I implemented the game as a port of a game called Explosion, written by someone called D A Hogg in some wonky kind of space-cadet BASIC for an ICL mainframe some considerable time ago. I don't know whether he invented it, or whether it was in Scientific American or what (If you do, please tell me). Even in version 1, Automaton Wars possessed many features which Explosion didn't - for example, graphics.
Occasionally, other versions of the same concept pop up. Acorn User published one a while ago called Atoms. I don't reckon any of them is a tenth as cool as mine ;-).


Unlike many board games, the state of play in Automaton Wars gets progressively less stable as the game proceeds. One school of thought holds that this means there are no good moves early in the game: so long as some of your pieces survive until the end game, they say, you've got as much chance as anybody else.
This may be true; however, even if there aren't good moves, there are definitely bad moves, and very definitely some good "structures" you can build yourself.
For instance, with a configuration like this, the blue player can blow up the red stack on the left, but the red player can't blow up the blue stacks on the right. The subcritical stack in the middle acts like a one-way firewall.

Downloading Automaton Wars

Just click here (40K). This version is in BBC BASIC and ARM assembler, and only works on Acorn RiscOS computers. If you don't have such a thing, you could try the Java version instead.
(K) All Rites Reversed -- Copy What You Like