KOTH Gozguy vs Mark 2407.0
Standard settings.
I hope Gozguy doesn't think it presumptious of me to call it at this point. I've glassed every enemy planet and have "lost contact with the Chin empire". It's true however that he does still have 1 (one) colony ship left, which may just about get to land its colony before being blown to hell by the two light cruisers that are a couple of squares away...
We started with only two systems between us. I pushed forward with missile ships as early as possible, and Gozguy - not being Ancient - probably didn't realise the danger until I was adjacent to his home system. I was able to block any expansion in my direction, and - after several attempts - break into his home system and glass his homeworld.
Gozguy was able to expand very fast in the other direction, and must have colonised around 2/3rds of the volume of the galaxy. However, after the loss of his homeworld he was never able to put up any serious resistance in space, and clearing up all those colonies became more of an exercise in logistics than anything else. I'm impressed that he carried on playing so long.
I think the three critical factors were;
1) I was lucky enough to have a much nicer home system than his, with two breathable planets in it.
2) Having Ancient, I had a big advantage knowing where he started and being able to dictate the border.
3) Gozguy was a bit slow to build warships once we made contact, and wasn't properly prepared to defend his home system. Or maybe he had resource problems - not sure.
Anyway, that's it (or, if Gozguy insists, we have one more turn to process

)
*strolls up to the crest of the hill, whistling*