The White and Black players each start with 13 Atoms of their color, and there are also 4 neutral pieces called Neutrons.
Click the green 'start thinking' circle to automatically randomize the starting position of the Atoms and Neutrons .
 
The object of the game is to get rid of your opponent's Atoms.
 
Atoms cannot move.
Each player can move a Neutron in any direction, but it must keep moving through all empty squares until it hits another piece or comes to rest against a wall. It then explodes and destroys all atoms of both players which are adjacent to it. Neutrons are never destroyed.
A player cannot move a Neutron that his opponent last moved.
If a move by either player leaves atoms belonging to only one player, that player wins.
If the last move leaves no Atoms of either player it is a draw.
If a player has Atoms left but has no legal moves he is stalemated and it counts as a draw.