This is Paul Shirley's first foray into the 16-bit games scene, having written 8-bit classics such as Confuzion and Spindizzy. Drawing inspiration from a wide variety of other games, Quartz is a progressive shoot-'em-up which revolves around the Lattice, an eight-way parallax scrolling Asteroids clone.
There's no plot to speak of, but the action is set in a world of Quarks, Hadrons and Neutrinos. Hadrons (yellow, red or blue big rocks) decompose into Quarks (similarly coloured smaller rocks) when shot - both of these are only found on the Lattice, which appears every other level.
Nautrinos, the product of shooting Quarks or whole formations of aliens, are used to buy any one of twelve types of power-up - but only when you've collected enough. Items you can purchase include eight-way fire, smart bombs, a flame-thrower, outriders, ship repairs and a pod which allows extra weaponry to be fitted. You eventually need one or more of these, because the standard issue pea shooter you're given at the start isn't very impressive.
Apart from the Lattice there are four basic game types, each of which scrolls in a different direction. The first is the Atomic Zone, combining a mixture of revolving fire-chains inspired by Super Mario Bros and some annoying alien attack formations. An asteroid field comes next, with rocks coming out of the screen towards you, followed by the Lair, a world of mechanical and electrical enemies. Finally, there's the Organic Zone, populated by insects and pulsating, pus-spewing hearts. Nasty stuff.
For all its graphical excellence and neat way of combining five games, Quartz is a little slow: it's more of a tactical game than a pulse-racing blaster. Even so, the variety of sub-games and the need to survive to collect enough neutrinos provides a lasting interest that more standard shoot-'em-ups lack.
Smooth and colourful eight-way parallax scrolling and a great soundtrack make Quartz immediately appealling, a feeling that doesn't wear off for some time.
It borrows a lot from other games, most noticeably Asteroids; but, like everything Paul Shirley does, it's beautifully presented and very addictive.