Multiplex is something of a cross between Beast's monster-squashing action and Pyro II's explosion-happy pyromania, much like those two games, it's rendered in colorful ASCII graphics. You, the player, find yourself in a series of mazes populated by roving monsters - all of whom must be killed. One way to do this is to crush them with the assortment of pushable walls scattered throughout each level. The second (and more entertaining) method is to step in close to them, which causes them to self-destruct in a dazzling explosion.

This is best done carefully, because the explosions are deadly, if other monsters (or eggs) are caught in the blast they'll explode as well, setting off chain reactions. Later levels feature large, scrolling playfields, packed with faster enemies that detonate in bigger blasts: the slightest carelessness can get you toasted in short order. If you die, you get two chances to continue from the same level, but your score is reset to zero.

Levels can be modified by editing a plain-text .ini file (which is fully commented).