So, I played a round of Betrayal mode and was able to finish it on hard/hard within about three hours. It was a little bit underwhelming as far as challenge level goes - I simply used all my initial credits, plus about 35k from destroying pirate bases, plus a whole bunch from "expand usable land area" to boost my space power multiplier way up high. At this point, I was able to walk all over everybody's fleets personally (and let's not even mention my robots' combat strength). The one thing I noticed is that, whenever a race declares war against some other race that's not me, it'll immediately go for the destroyed hydral planet, which was controlled by me. So, maybe I'll go back at some point on a harder difficulty, but that's in the distant future.
Meanwhile, I started an Invasion game. Now this is tough! The Obscura deliver quite a lot of damage when they hit, and are quite tough as well. The best defense I've come up with so far involves the cloaking device/cloaking field combo so that I stay cloaked. But then I have to chase the bastards down which takes time. So, I need to boost my space power to prevent my ship from exploding when hit by a corn flake, but guess what: my usual money making methods ("Expand Usable Land Area") take too long, and you only start with about four pirate bases (so that's 14k credits, not really enough). The Obscura gave me maybe a year before they went for the second world with overwhelming force, which I simply can't hold back.
So, who's got tips on how to keep the Obscura down?