I just got the Glactic Plague mega-event: All planets start loosing population until you discover the cure technology. I found the cure and decided not to share (it doesn't look like anyone else is even trying).

The result? I'm going on a massive sweep through the galaxy, sweeping up every planet in my path. With their reduced populations, I can get any planet (including homeworlds) with a single transport. I have about double the population as all my oponents combined. I'm pretty sure this needs tweaking, but in the meantime: Awesome!

Also, I'm best of buddies with the Dread Lords. We have treaties!