Dark Side

To complete the mission, the player has an arsenal of beam weapons mounted on a jetpack-equipped pressure suit. The aim is to destroy all ECDs in a specific order and avoid capture or death by the traps left by the terrorists. ECDs are connected to power lines and can only be destroyed when all preceding ECDs have been deactivated, otherwise they will instantly regenerate. The player has a limited amount of time available to complete the game, based on the energy accumulated in Zephyr One.

When the weapon is fully charged, the beam is fired, destroying Evath, and the game ends. As the player destroys ECDs, the charge accumulation rate is reduced, allowing more time for the player to complete the mission.

The game is set on the alien moon Tricuspid orbiting the planet Evath. Terrorists (the Ketars, the villains of the previous game Driller) hijacked the moon's facilities and built Zephyr One, an immense beam weapon on the moon's dark side with the purpose of destroying Evath. The player is a government agent, sent secretly to the moon's surface with the mission of deactivating the weapon before it becomes fully charged. This is accomplished by destroying a power network in the form of ECD (Energy Collection Device) columns, dotted around the moon and connected with power lines all the way to the beam weapon.

Dark Side was the second game to use the Freescape engine, which allowed the production of full three-dimensional environments using filled polygons in which the player could move around freely. It also gave the player the ability to look up and down, as well as rotate left and right, something which was rare amongst 3D games of the time. The same engine was used for Total Eclipse, The Sphinx Jinx, Castle Master and Castle Master II: The Crypt.