I've just won a game as my human civilization... althought this description at the end doesn't really describe what happened. It was more of "I made an alliajce with one civ that was willing to do so and wiped out everyone else"
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But I can easily say that this game has been won by one type of ship: fighters. I think they are the best class. Thry are cheap, can be produced from early game, can be used in swarms and their Evasion bonus gives them better chance at survival than their low HP would otherwise suggest.
Cruisers became nearly useless once enemy started using Nanite Repair Cloud.
Here are some screenshots from this game:








