Psycastria is a Uridium clone written by Gary Partis and originally released on the BBC Micro.
The Psycastria have constructed four different types of installation, one on land, one at sea on a giant carrier ship, one on the surface of the moon, and the final one in deep space. It is in these installations that they store their energy supplies in circular pods. You, now endowed with the skill and cunning of the famous Boggles, are in charge of a highly manoeuverable craft capable of stunning mid-air changes of direction. Using just your basic astro-cannons you must attack each installation in turn, avoiding the high buildings that stand out from the surface. However the Psycastria will put up a strong defence with their bizarre shaped fighters.
You can cause a [sic] much damage as you like to the installations, but your main aim is to destroy the 10 circular energy pods, then land on the main landing strip, signified by the leading arrows on the left hand side of the strip. Once you have landed there is a sub-game in which you can try for a bonus by destroying aliens which fly across the screen. When that is over you may take off to the next screen. You start with 3 lives and get an extra one every 30,000 points, and your points score determines your eventual rank (10 levels from Novice upwards)...