Crusaders Of Space: Open Range

Just when you thought the alien invasion was successfully fought off once and for all, new waves of alien scum come in numbers far greater then 5 years ago. The government is alarmed.

An abstract from an official intelligence report:

Our satellites have located as many as fifty alien interceptors rapidly approaching planet Earth. Detailed analysis of the digital image data revealed a larger object as well. Without a doubt, it's the Big Brain, thought to be killed 5 years ago. Looks like we should start a search for a new hero right now!

Who is going to win this time? Will the humanity be able to form a force capable of stopping the attackers? Or will all humans be enslaved by an alien civilization that came from a far away galaxy?