Stardust

Stardust is basically Asteroids, but with a lot of gameplay modifications. There are 30 standard levels split into 5 worlds. The 6 levels a world is made of can be completed in any order. However, you must fight an end-of-level bad guy once you have finished the 6th level of a world. While each level has the standard disintegrating rocks to destroy, all but 2 of them have extra bad guys, with a range of attack patterns.

There are a number of different weapons available, which are collected by moving your ship so that it crosses their paths as they float through space. Each of these can be powered up - some weapons start strong but can't be powered up as much as others; fortunately you can power up one weapon while using another. Extra lives, shield enhancements and a smart bomb are also on offer.

Along with the standard levels, there are also 4 tunnel levels, which involve shooting what you can and dodging everything else as you dart through a ray-traced 3D tunnel, and 2 optional Thrust-style bonus levels in which lives can be won or lost.