Swallowed star is the adaption of the chinese webnovel Swallowed star by I eat Tomatoes. I'm just going to start by saying that I have read the entire webnovel and I've restarted it very recently, so I'm a bit biased. Swallowed star WN is an excellent story, at least in the beginning. I enjoyed the first ~200 chapters immensely, and it's really different from the average xianxia since it's in a sci-fi setting. As of episode 8, the anime has managed to adapt the characters and monsters quite well. The art is pretty good and the sound is good as well. But my main problem is that I'veread the webnovel. Unfortunately, they have decided to keep most of the events that happen in the novel, but completely changing the way they happen. I don't think it's a good thing but I could have accepted it if the way they did it made sense, which isn't the case.
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Spoilers from episode 8 :
Xu xin is in danger outside the city without any protection. Luo Feng and his squad goes to rescue her. Except that Xu xin comes from a really important family and is a direct descendant, so how the f*** would she be outside without protection. Not mentioning the fact that she is a university student so how is she outside to begin with. Also, the main job of warriors is to hunt monsters when they go outside, so they don't usually wait for a mission.
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Anyway, so far I would say the anime is great. Too bad I have to take 2 points because of the nonsense modifications, 8/10.

Edit after finishing: Unfortunately my impressions after episode 8 were right. It's better to consider this story as completely different from the novel. Most events and characters are the same but the way they happen is way different, and sometimes don't make sense at all. It's really sad because it would have been way better if they just decided to stick with the story.
Overall I would say it's a 8 only if you haven't read the novel, because it's still pretty good. If you did and you remember it, it's closer to a 6 and I'm not sure I'd recommend it.