From the Inlay (Spectrum / Amstrad version):
Played between two droids on a specially constructed pitch, Vectorball is an exciting blend of many different traditional games.
Using all your skill, guide the droid around the pitch in an attempt to score more goals than your opponent.
Five different pitch types to choose fro, each with its own characteristics. Each pitch will require a different skill and combining all the various skills will enable you to master the game.
The inlay describes the game as "a complex blend of speed of Ice-Hockey, the precision of Netball and the complex curves of Crown Green Bowls". I would suggest that there is a bit of crazy golf in there too!
The game is played on a pitch, represented by a vector mesh (hence the name). The pitch is not level, but has various peaks and troughs. The higher the level, the more complex the topography. At each end of the pitch is a goal, through which a ball must be fired in order to score a point. The whole pitch is larger than the screen, so the viewpoint scrolls to follow the ball.
Like Netball, when the player has the ball, they must not move. Instead a strength and direction of shot is selected (the strength of shot is indicated by the extension or retraction of the droid's neck). In addition when the player is holding the ball, a timer counts down. If the ball is not played before the timer runs out, then the ball is automatically fired.
The aim is to use the undulations of the pitch, along with bouncing off the walls to guide the ball past the opponent and into the goal.