Sectoris Sky

At first shoot all the domes, and be sure to pick up all the ''rate'' cells or your ship just keep shooting - but will be too slow. Use the early stages to pick up "balls" and master diagonal shooting, but avoid "winos".
Kill the Sentinel by shooting at it until the dome opens and then shoot based domes, which it is best to simply dodge.
The "Space Invaders" in the manic last part.
Also be aware of the small aliens at the side, and take them out to reduce the amount of bullets in the air. Keep moving and blasting.