Tyrian

The Good
Essentially the last word in PC-based vertically-scrolling shoot-em-ups, this arrived just as the PC world was going mad for 'Doom' and its ilk. Graphically it's very nice - big sprites zoom around smoothly over colourful backdrops, and the sound and music are also top. Best of all, there are loads of hidden bits - from sub-games, to banana-bombs, to a clever segment in which you play the game in a capturedenemy fighter.

The Bad
I seem to remember that it wasn't all that tricky to finish, although the hidden bits helped extend the lifespan. It might be quite hard to register this nowadays, although a 'sequel' was produced quite recently

The Bottom Line
A classic, 'Terra Cresta'-esque vertically-scrolling shoot-em-up with lots of hidden bits.