Kabloomy, use Disruption every time he replenishes his focus. He won't one shot kill you then. You'll need high speed to ensure you hit him with it. After that it's just a slow fight to the end. Farm the last boss in the second last zone for his uniform. It'll up you're speed by 40 points and is a big help.
Great game, fun and challenging. I gave it four stars because IMHO the last level wasn't as difficult as the previous two. Perhaps if you switched the lvl's around from 10, 11 and 12 to 12, 10 and 11 the step up in difficulty would be more fluid and the end would be more of a climax. Would love to see a sequel maybe with a level editor feature.