Intensity is an arcade game that requires quick thinking. Played on static (non-scrolling) screens, the objective is to rescue colonists from a space station under siege by hordes of mutating alien creatures. The player controlls a surface skimmer craft which they move around the screen. Pressing and holding down the fire button lands the craft, instructing the nearby drone to move to that location. Nearby colonists then rush towards the drone to be rescued.
The skimmer has to avoid colliding with the drone (which always proves fatal!), whilst deliberately hitting the aliens that appear and fly around the surface of the space station. Only when the exit flashes can the drone be directed to the exit and thus complete the layer.
The first few layers are relatively easy, although the frequency that aliens appeare increases as you complete each layer. Raised obstacles on the surface of the space station on later layers make the game even more challenging. The basic skimmer has to be steered around these obstacles manually, but upgraded craft have the ability to climb higher as they fly, to help avoid a collision.
Starting at Gamma layer one, the player has to progress through each layer. The number of rescued colonists dictates where the player is taken next once they survive long enough to exit the layer successfully. Each space station is divided into five rows of platform, with each one sixteen platforms wide. The layers are labelled using the Greek alphabet (alpha, beta, gamma, delta and epsilon).
Intensity is one of those grossly under-rated games that slipped through unnoticed because it was released for the Commodore 64 and Sinclair Spectrum near the end of the 8-bit era. It's simple to play yet surprisingly addictive and frustrating in equal measure.