Now birds replace the Invaders
In Birds Of Prey, you control a laser base at the bottom of the screen while overhead a rectangular formation of birds march from left to right and back again.
Sounds familiar? This is yet another variation on the Space Invaders theme although in this case the formation doesn't work down the screen until it squashes you flat. Instead birds peel off, drop down and belt round an oval track just over your head dropping a steady stream of bombs.
From time to time one dives down in an attempt to crash into you. If it succeeds you die, but unfortunately the bird doesn't, so when your next man pops onto the screen the same bird is already weaving down again to have a go.
Whatever difficulty level you choose to start - and there are 10! - each time you clear a screen you move up a level. This increases the maximum number of birds which can be in orbit at any one time and also the number of droppings (sorry, bombs).
You get a bonus life each time you succeed in clearing four screens.
Much thought has obviously gone into the graphics and sound and when things really hot up the screen has the appearance of a major fireworks display.
It is frustrating to have to specify the starting level and method of control (joysticks or not) at the start of every game.
The program will accept input from joysticks, but is designed for what I believe are known as Clare's joysticks. Mine are the BBC variety, and consequently work in reverse. The keyboard controls are also awkward - A for left. D for right and S for fire.
If you already have several versions of Space Invaders you probably won't want to rush out to buy this one. But if you are still looking for a game of this type, Birds Of Prey deserves serious consideration.