I played a good 10 hours or so of this during the free weekend.
I went in thinking this would be yet another Amplitude game. It would look gorgeous, have fantastic setpieces, beautiful UI, and set itself up to just blow you away at first glance and for the first few hours. Then after the veneer wears off, you'll find a really shallow baby's-first-4X with awful AI and simple, braindead mechanics that just don't go anywhere.
And that's basically what I got. It's a lot better than Endless Space 1 at least.
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I find this is a big issue with these modern 4Xs. They put so much into making a great first impression that they completely forget the rest of the game. It's how it is for Stellaris for example. I played a few campaigns in this from hard to a few levels higher than that and not once. Not a single time. Did the AI ever declare war on me. And it's not like there's anything to do in this game past the exploration stage other than to war with people. Even in the quests which deliberately force you to fight the AI, the AI never fought me and just did nothing. The pirates were more of a threat to me than any of the AI factions. Not that increasing the difficulty improves the AI to begin with, since this game is one of those where the AI is exactly the same at all levels, just at every level above "normal" it has more and more resource cheats.
Then there's all the dumb, half-assed mechanics that seem like they have a lot of promise at first but don't turn out to be anything but half-assed. The diplomacy for one barely even works with the AI. If this was idea of a patched feature, I have no clue how terrible it must have been at launch. Combat has all these fancy buttons all over the place, but they don't do anything and you'll never need to refer to them. Trading is bloody dumb in that you connect a trading company HQ with a subsidiary you build somewhere else. That's it. The late stage of the game is just as unbalanced here as it is in all the other Amplitude 4X games, where you end up with infinite dust and whatever so every single turn you just spam the buy everything button over and over again. Don't get me started on ground combat.
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All in all, I think it's better than Endless Space 1 and worse than Endless Legends. I'd put it at slightly behind Stellaris, but only because at least the AI in Stellaris will fight you. They're both frigging bare bones baby's-first-4X games, though one is noticeably getting better (and more expensive) every two months.
This does have planet destroyers and, more importantly, cutscenes for them. So I might actually rank this higher than Stellaris just for that.