Liquid War is a free software multi-player action game based on particle flow mechanic.
Thomas Colcombet developed the core concept and the original shortest path algorithm, the software was programmed by Christian Mauduit [fr].
Since a particle can only fight in one direction at a time (towards its team's cursor), a player that surrounds its opponents will have a distinct advantage.
The computer AI's "strategy" is to constantly choose a random point in the enemy and move its cursor to it.
The Liquid War shortest path algorithm was invented by Thomas Colcombet before the game itself in Spring 1995.
As of July 2008[update], the current stable version is 5.6.4 and is available under MS-DOS, Microsoft Windows, Mac OS X, Linux and FreeBSD.
Its author, Christian Mauduit, has announced that a complete rewrite is in progress to produce version 6.0, which will abandon the Allegro used for 5.x releases for a full OpenGL implementation.