Well, I was able to get my alliance with the Drengin...which of course meant I was promptly dragged into war with the Altarians, then the Arceans, and then the Torians, so I got one alliance and a three-front war! Fortunately I was "behind" the Drengin and let them do all the heavy lifting (though I did indeed send out some Rangers on raids to pop starbases and orbiting transports).
I also already had ten constructors en route to the Arcean border, with evil intent. I sent five constructors up to the nearest Arcean world, built a terror star...and discovered I couldn't attack because I was out of range! [Hmm...in range for constructors but out of range for terror stars; seems a pointless restriction.] So I diverted a constructor and built a "relay" starbase...then blew up the Arcean system. No resistance from the Arceans, even as my terror star lumbered over to the Arcean homeworld. Arcea KIA. Building that terror star put me about 3Kbc in the red, but about this time a new minor (the Furan) obligingly appeared (the only one for the whole game), and I used my trade goods to put them in hock for the rest of their natural lives (469bc for 50 months or some such).
Meanwhile I sent another 5-pack of constructors toward the single Torian system. About this time, Torian warships blew up an economic starbase that I was fond of...so I retaliated by blowing up their home star! [Served 'em right, the lizards! :notsure: ]
About this time the Drengin conquered the Furan...and made peace with the Altarians! (That was a mild surprise.) So I made peace (couldn't get much of anything out of them, pipsqueak that I was) . . . while my two terror stars crept slowly closer. The border Altarian worlds were trembling under the weight of Drengin influence, and started to flip.
Throughout this period I was running about 50/50 military and research, pumping constructs for trade SB(and Avatars to protect the terror stars), and trading new techs for more techs. That research and trading was basically just going through the motions; it had little impact once I had terror stars, and I think I had to research avatars myself. Just at the end I researched Overlords, but didn't bother to start any. [The Drengin had LOTS of Overlords! But the Drengin never once invaded an Altarian world; they only invaded the minors.]
The Altarians allowed my terror stars to lumber up to the outer two of their remaining three systems. Boom, boom. Then the two converged on the Altarian homeworld. When they were one parsec out, the Altarians surrendered to the Drengin, and I had my Alliance Victory.
So the advice worked, and my thanks to Sirian et al. This was a One Sector Challenge, presumably much easier than One System or One Planet, so I may have to try this again. The maso win was worth about 26K on the Metaverse...cancelling out my second maso win because I forgot this was from the same starting position. [Whups!] Onward and upward! -- HtL