1. It's not entirely 1:1 on the scale, but it does scale with the amount of players to keep it challenging. You will need to work together. Time to play shouldn't be significantly affected.
2. The AI does not change its tactics depending on wether you've found the core worlds or not. That's entirely AIP based. There's some "plots" that can be activated that affects end game, but that is only after you destroy a core.
3. After you kill an AI, that AI is dead. It can no longer do anything.
4. Hmm, I didn't even know they could be transported. But if they can, no they can't be blown up inside the transport.
5. Put ships in them, take transport to where you want to go, unload ships somewhere semi-safe. Easy really
They're FAST.
6.1. Umm...A LOT. There's a lot more ships, plots, AI-types and settings to toy around with. 2. Depending on expansion and settings you use: None to a lot.
7. Quite a bit. The difficulty setting affects AI intelligence up to 7, where it's at its full brain power. After that it's a pure "power-boost" up to 10. The AI-type can make for easier games (passive, defensive) or very hard (Special attacks/ships, overly aggressive). They're categorised though, so you shouldn't have trouble seeing which are hard and which are easy.
8. No. The general idea is that if you have to nuke, you're probably screwed anyway. Sometimes, they can be a life saver, but generally, they're more hurt than boon.
9. If you wonder; ASK. That's it.
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