Description from the back of the game booklet:
Beam Weapon is a futuristic battle scenario with orbiting killer satellites, tracked beam weapon transports and other high-tech space and ground battle systems. Beam Weapon is a fast, decisive action scenario that depicts the accuracy and sophistication of high-tech weaponry.
Game summary from review of the rules:
The game is a simple hex and counter war game in a futuristic setting, using a mix of space and ground units.
Combat is conducted using a standard combat table and a single die roll, based on the difference between unit offense and defense values. The die result can potentially destroy either the attacker or defender (but not both) based on the odds.
A simplified concealment rule is used for ground units (including bases), the type of unit remaining unknown by the opponent until engaged in combat or spied on.
The goal of the game is the elimination of the opponent's three immobile bases.