Alien Highway was written 'by popular demand' as a sequel to Highway Encounter and is a souped up, modified version of the original game.
This time your target is the Alien Empire, a vast complex which is essential to the aliens' survival. Once again, you are in control of a droid, or Vorton, but this time there are no lives a single robot is supplied and it has to be recharged from power points along the highway, as contact with the aliens or their weapons saps vital energy.
The ultimate aim of the game is to shove a mightily powerful explosive device The Terratron all the way down the highway to the gates of the Alien HO where it can detonate and rid the world of nasties (until the next game, at least). The Vorton accelerates forwards at great speed but slows down quite slowly if left to its own devices, so some nifty control manipulating is called for to make it behave according to your wishes. As before, the Vorton has to be pointed in the right direction and then moved.
The Aliens have learnt their lesson from Highway Encounter the road to the Empire is littered with obstacles and alien nasties. To add to the fun, the edges of the highway are electrified and burn a clumsy Vorton touching them to a frazzle. Once again, certain objects on the roadway can be moved by firing at them with your lasers and then used to block the path of some aliens, ensuring a safe passage for the Vorton and Terratron.
'Hairy lasers' are still fitted as standard equipment on Vortons, and make suitably short work of aliens. En route, the Terratron must be re-charged seven times so that it's in tip-top condition when it arrives at the Alien Empire: keep an eye out for the Regeneration Stations.
The status area at the bottom of the screen shows how low your energy levels are getting, the time that remains in which to complete the mission and how many of the seven re-generations your Terratron has been given. Without the full complement of regenerations the barrier guarding the alien complex is impassable.
The new highway spans thirty screens, as before, but this time there's a random element which governs the way the game sets up map-makers won't have it all their own way!