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It takes around 20 hours to watch all 54 episodes of Adventure whereas the game can take 60-100, depending.I actually recently played through the English patch, and my quickie review is that fights take far too long. But if you have access to the Japanese version of the anime, just watch that instead. My final thoughts? If you're the type to enjoy grindy RPGs, and/or you've never seen Adventure in its original Japanese, then it's a fine way to experience it. It's just a much more compelling way to absorb the plot than a fairly average JRPG copy-paste of the anime. Plus, the simple act of being a novel means that we're inside the characters' heads more at basically any given moment.
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Things such as spending more time at the camp in the first chapter so as to actually properly introduce its characters, trimming down the events of repetitive early episodes so as to get to the meat of the plot quicker, explaining where the Dark Masters were the whole time, establishing greater world building by tying the Harmonious Ones into Adventure's plot so they seem like less of an asspull in Zero Two, etc. Honestly, the novelizations did more to improve the plot of Adventure than the game did by fleshing out the story in ways that actually mattered rather than adding side chapters just for the sake of it. If you want Adventure's plot verbatim, but stretched out to 90-ish hours and without any of the cinematography, then sure, Adventure PSP was "improved." I found it to become a huge slog by the halfway point.
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They added nothing to the overall plot other than some occasional decent character building, but most of them were entirely forgettable. There were extraneous side chapters added, but they were just that: extraneous. I wouldn't say "improved." A lot of the game was literally word-for-word from the anime's script, except now instead of actual animation and movement, we get talking portraits, still backgrounds, and text boxes, and maybe occasionally some low-poly character models performing rudimentary animation loops. The side chapters are new stories, but none of them add anything of any real substance.) (But the tl dr is that the story is basically 1:1 accurate to the show, but with less interesting presentation.
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I played through the game last year, and I'm going to copy-paste a comment I made about the game a while back.
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