Note: This Flash game is Nintendo Wii compatible.
This Flash game is in no way associated with the Uniwar iPhone game. This game predates the Uniwar iPhone game by nine years.
I know it's freakin' hard, but I have beaten it under the current flash player (it was much easier with player 4 as it ran slightly slower). The key to defeating the boss is not to worry about the ships. The damage they do isn't that much, but to throw everything you got at the cannons, then at the mothershop's bulb. As for the miniboss before it, just shoot the head all you can, as fast as you can, and dodge the mech as it flies at you. For the miniboss at the very end, the truck is filled with munitions, so obviously, hammer the crates all that you can and it'll blow up with you flying right into it.
Although this level hadn't been graphicslly updated like the first level, feel free to play it anyway.