Anachronox is a labor of love that suffers in the gameplay department.
The game's writing, characterization, and storytelling are all top notch, and the cutscenes that go with that story are all directed fantastically (to the point where the game was edited into a film at one point).
The game's environments, while occasionally not the best graphically (specifically areas like the canyons of Democratus), are still very unique and well designed, and this is supported by great sound design and a phenomenal soundtrack (highlights for me being the theme of Hephaestus and Stiletto's theme).
The one place the game suffers, unfortunately, is in its actual gameplay. Combat is slow and not very strategic (though the idea of moving around the battlefield and interacting with the environment is a great one), only two or three dungeons are more interesting than a leisurely walk, and the puzzles can occasionally become tedious and annoying.
However, I don't think Anachronox's gameplay failings override the rest of the game, which is absolutely fantastic. If nothing else? Absolutely worth watching the movie edit. Otherwise, highly recommended for those who enjoy rich worldbuilding and witty writing alongside a great story.
Oh, and one final thing, this game easily has the most unique party in any RPG. Without question.

This is easily the best Xenosaga game.
That's a strong way to open a review, but coming directly off of Episode II this was a massive breath of fresh air. So many improvements have been made between not only this game and Episode II but even things from Episode I that, while I said in a previous review that one might be better off watching Xenosaga rather than playing it, Episode III is the exception.
I'll begin with the usual non-spoilery story section. Despite an entire part of Xenosaga's story essentially being cut due to the series' overall poor sales, the year span in-universe between Episode II and Episode III is easily accesible via the game's great new Glossary system, returning even better from Episode I. Being able to access story events and terms while cross-referencing other relevant terms is great, and the database updates as the story goes on to help quell a lot of the confusion Xenosaga's narrative is famous for. The story of Episode III is easily the best constructed of the three games, with a lot of beautifully animated cutscenes and even fully voiced text boxes that conclude the story of this trilogy rather satisfyingly (while also leaving room for a sequel should the day ever come). This is supplemented by a lot of returning voice actors from Episode I and even some new ones (Steve Blum and Yuri Lowenthal can be heard within the first hour, for example), and the voice direction is miles ahead of Episode II, leading to this being my favorite game to watch the story of.
But the story isn't the only thing that has been improved in Episode III. Finally, FINALLY, the combat has been fine tuned to be fast and fun to play both on foot and in the E.S. Gone is any semblance of the combo system, instead just having regular attacks and Techs as separate menu options. The Break system has been balanced as to not completely crowd battles, and the Boost mechanic also FINALLY lets you boost while a character is on the turn order, something that bugged the hell out of me in Episode II. The Boost meter has also been given another purpose - every character has special attacks that take Boost to perform. These specials have elaborate animations like the Techs of Episode I, but don't take an eternity to play out and don't happen every turn, making battles feel unique while still being fast. There wasn't a point in this game where I felt bored fighting a regular enemy.
The E.S. have also been generally improved over Episode II. For one, the dungeons where you ride them are much more elaborate than the straight lines from Episode II, with actual puzzles and interesting areas. The combat is also a lot of fun, with the Anima system adding layers of strategy more than the mechanic in II that...I honestly don't remember the name of, but was used for a whole two attacks on each E.S. that weren't much better than your regular attacks. The co-op, ambush, revenge, and counter systems are also fun to play around, and outfitting your E.S. with specific weapons that use specific amounts of fuel reminds me a lot of how Skells would end up working in Xenoblade X (though obviously in a turn based system instead of the Xenoblade real time combat). The E.S. fights were also a lot more challenging, with certain ones near the endgame being among my favorites in the entire Xeno franchise now.
The game isn't without its issues. For one thing, like Episode II, while you can switch out party members at any time in battle, you can't switch anyone out if they're dead, meaning you need to revive them with either the high EP revival skills, the common Revive M item, or the Seven Moons item that decides to stop appearing in stores partway through the game. This can be annoying during the game's harder boss fights, especially some of the E.S. bosses near the endgame. Another issue is with Shion's characterization. For the first time, the person billed as the main character actually feels like the main character of the story (in the previous two games, while Shion begins the story, Jr. is clearly the focal character due to his strong connection to the main villain). This is a good thing by itself, but Shion's characterization has taken an...odd turn. While in the first game she was headstrong (if a workaholic) and was...there in the second game, in Episode III she acts much more hostile towards everyone in the party for...no discernable reason? I understand that the events between Episodes II and III caused her to undergo some change, but the amount of annoyance she expresses towards a good portion of the cast makes her uncomfortable to be around at times. There's also a certain story event that many have commented on that make her a divisive protagonist, but I don't want to get into that here for want of no spoilers. All I'll say is that I understand what was trying to be conveyed in that scene and like what they were trying to do, the execution is a bit lacking.
I'll end this review on a higher note: the MUSIC. While Episode I lacked music in most of its areas and Episode II's OST was a very mixed bag, Episode III's soundtrack is nothing but hits for me. As early as the first dungeon you get the jazzy "Rolling Down the U.M.N.," and the hits keep coming after that. Personal highlights for me are the aformentioned song, both versions of T-elos' theme, and the rendition of Episode II's "fatal fight." The soundtrack is simply incredible, and worth a listen on its own merits.
Overall, Xenosaga Episode III: Also sprach Zarathustra has been a welcome surprise for me after binging this trilogy (and Xenogears). While it doesn't reach the heights of Gears, or even some of the Blade games, it's a solid RPG that I would highly reccomend playing. A solid conclusion to a troubled trilogy.

My hands are in pain but the adrenaline rush is more than worth it. Incredibly fluid movement, fun gunplay (partially due to the movement), plenty of fun exploration and secrets, and incentive to perfect each stage leads this to be one of the most addicting games I've ever played. It requires you to learn its mechanics in each stage and will regularly test you with its boss fights and in-level challenges. Multiple difficulties also add to this game's massive replay value. Cannot recommend enough.