After several months I've eventually finished this game. I've played other 'mixed-genre' visual novels before (Danganronpa, Persona and Ace Attorney for example) and generally enjoyed them. And yes, I did find 13 Sentinels interesting and fun to play for the most part. I'd definitely recommend trying it.
However I think the way the story was presented made an already complex story unnecessarily confusing at points. For context, the story is told from the perspectives of 13 separate protagonists, in short chunks. Because of the way you unlock different sections of the story (either by getting to a certain part with one character, or making progress in the battle mode), you'll be shifting through each of the individual stories constantly.
In some ways this is a neat way to tell the story and keep things mysterious, but when there are so many characters with branching storylines it becomes a lot! Granted, it probably didn't help that it took me several months to get through it - that was mainly the result of the battle mode feeling like a chore to play at points.
Despite all this I did really like where the story went, and it mostly makes sense after one playthrough.
Some aspects of the story that I'm still unclear on:
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The whole deal with the multiple versions of Morimura/Iora/Chihiro. Morimura was a previous version of Iora from a previous loop? And she wanted to implant her memories onto Iota?
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Similarly, Ida's story. Amiguchi is another version of him?
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Why was Chihiro trying to force another loop? She wanted to be the one in control somehow? And similarly, why was this the final possible loop?
If you like visual novels, confusing anime storylines and science fiction you'll probably enjoy this game. Visually it's very impressive with some beautiful animation on the characters and painterly backgrounds. The voice acting and music is excellent, perfecting fitting with the tone of the game. It's likely not for everyone, but if you're willing to accept its shortcomings it is worth playing for the fascinating story alone.
It definitely gets confusing. I didn't enjoy the game at first, and I think experiences can vary widely depending on a player's chapter selection. I ended up with a stretch of all school life stuff early on, with more of the school crushes and inconsequential dialogue than the more interesting sci-fi bits (I hated Megumi's chapters). Putting off Natsuno's was also a mistake, as she ended up being my favorite character. The game has grown on me since.
The stuff with Chihiro gets a little wild, but it essentially all boils down to
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a difference of opinion in how to get out of the mess, and the access to do so. Chihiro wanted to blow it all up again, and she needed to put herself into Iori to loop again with herself intact. It being the last loop is simply a resource problem. The simulation had been running through many loops for an untold number of years (likely many millennia). The idea of another loop being possible only by scaling it down (and presumably killing some of them) was a big part of why the others wanted to make their stand at that time.
Yeah I agree with all that! Definitely a bit too much school life stuff near the start. The story starts to get properly interesting around the halfway mark, but also branches out so much that it's hard to follow. I'd love to see a similar game in this setting, with an equal complex story but told in a more standard way.
Also yeah Megumi's part kinda sucked. Didn't ever get interesting.
I absolutely loved this. Hated it briefly at first, and IMO the real-time strategy parts are way too easy to the point they end up being dreadfully boring, but the story parts were exciting to me and I loved noticing things as they slowly came together.
Bought it on a whim, ended up recommending it to friends who also in turn loved it.