Zapshot

Zapshot is a DOS shooter from 1986, back when the PC could barely do anything and its games were written by enthusiasts for four-colour CGA. The premise is familiar to everyone: your ship sits at the bottom, moves sideways, and endless waves of alien craft roll down towards you, to be shot before they shoot you.

One idea sets it apart from dozens of similar clones — overheating. You can hold the fire button down indefinitely, but the beam heats up, and overdo it and it destroys your own ship. So you do not shoot constantly, you ration it, watch how much the weapon will take, and let it cool between waves. That turns a simple arcade game into an exercise in restraint, which for 1986 is smarter than the title suggests.

Above everything, a mothership drifts across the top of the screen. Hitting it is difficult and takes several shots, but it pays well in points — and deciding whether to risk firing at it instead of clearing the wave below is the second thing that lifts this above average. Six difficulty levels are on offer and the game keeps a separate best score for each, so improving actually means something.

The rest is exactly as austere as you would expect: four colours, beeping through the internal speaker, no story whatsoever. Anyone with no taste for games that look like they came from the PC's first year has no reason to launch it. Anyone who does will find a surprisingly functional little thing built around one good mechanic.

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