The “Sonic is dead” aspect is obviously the main thing that’s supposed to reel you in (and it works). You go in, expecting a quick 20-minute-ish April Fools laugh, but… It turns out to be more than a simple joke. It’s a genuinely nice little story. It’s clear a lot of love was put into this visual novel. It’s chock-full of fun details and references to Sonic’s other adventures.
Of course, being a visual novel, the main focus is the story and characters.
We have some new characters exclusive to this story - the conductor, the protagonist, and… the train. I’ll only cover the protagonist here.
They’re your typical relatably socially awkward protagonist, but… The writers turn that up to an 11, to the point of absurdity. I personally really love that, but some may find that annoying. At many points the game got me thinking “me too, buddy” at their internal monologues and funny antics.
And as for the already-existing characters… I think their characterisation was really good! Honestly, I don’t have much to say here.
The plot was great, in my opinion! The mystery is not very complex or hard to figure out, but the game doesn’t treat you like you’re incapable of solving it yourself, which is something even big commercial games struggle with. Going along and solving the mystery is really fun!
Apart from the main, “intellectual” side, there’s also the sonic special stage-style “THINK!” minigames. They’re alright, they’re a fun distraction from the reading. And if you just do not care for them, or find them frustrating, you can tweak almost every difficulty aspect in the accessibility options, which is fantastic, in my opinion. I personally did play through each one of them, because they were a nice little challenge.
Oh and I should mention - the artwork is just gorgeous. The character sprites are so good, and the backgrounds are beautiful and so full of fun details.
It’s a quick play/read: I finished it in 4-5 hours, according to Steam; in one sitting. It is a fun one, though!
If you’re a Sonic fan, I think you’ll enjoy this, if you’re not, I think there’s some enjoyment to be had here too - the narrative is from the perspective of a character who has heard of Sonic and his friends in passing.
This game’s a treat, and was obviously made with a lot of love for these characters and the franchise. It’s awesome that SEGA let the team make something like this, and release it for free.

Some parts were really irritating but it was all worth it. It took me a loooong time to finally beat Rush but I'm glad I did!
Some of the level design is pretty questionable (some parts punish you for going fast out of nowhere) but overall I had a ton of fun with this game. The special stages were really cool (even if the later ones were a bit of a pain)
My favourite thing about this game is probably the visual presentation and the music! So much style and charm.
My 2nd favourite Sonic game that I've played so far, and one of the two I can say I completed. (I've played Sonic 1, 2, Adventure and Mania, only completed Sonic 1)

A disappointing experience, as someone who's played Katamari Damacy and We Love Katamari. I mean, yeah, I suppose it's still a Katamari game, but it just feels like... something is missing.
I do like the jump and squash and stretch mechanics, but I feel like they make the game a little too easy to control (with Katamari, I think learning to control the katamari efficiently, despite how hard it is initially, is part of the fun).
The levels are fine enough, understandably they couldn't be really big, since this is a handheld.
What really irks me and keeps me from fully enjoying this game is how strict the time limits are. In the original and We Love Katamari, you had plenty of time to familiarize yourself with the stages and still be able to get a good score. Here, even if you try your hardest to optimize your route and stuff, you won't get more than 70/100 points. Oh, also, this game has an actual scoring/rating system, instead of the King just saying what he thinks about how you did. I don't like that.
The levels are also very repetetive. Very little variety in level goals.
As for the presentation, yeah it's totally weird and uncanny, but honestly I'm all for it. Katamari games always have that kind of wacky vibe, and here it's turned up even more. But the other games in the series that I've played do it better in my opinion.

If you just want some Katamari action on your Vita, this is fine, I suppose, but I think you're better off just playing earlier entries in the series. (Keep in mind, I've only played Damacy and We Love Katamari apart from this one)

Make no mistake, this is a furry porn game. There are several unskippable sex scenes, and characters are frequently in the nude. But this is the most well-written furry porn game I've come across. And a great visual novel overall, but yeah. You should know what you're getting here.

I've never been this invested in the politics of a fictional world. The worldbuilding centers around some really interesting concepts. Not all of it is even remotely realistic, but it doesn't need to be. It focuses on the "game" of politics, on social relations, information, blackmail... political drama.

The characters are really well-rounded and fleshed out. Was genuinely invested in the romance between the protagonist and Amicus. And it was interesting to see the other characters gradually reveal more and more of themselves.

I'm asexual, and as such found no appeal in the sexual content, unfortunately. If it appeals to you, or you can at least stomach it, I can highly recommend reading this. It's a great story.

Great game, though I liked Origins better. The main hub and levels don't quite have the same whimsical feel Origins' levels had, the story is also weaker, it's barely there - though likely you're not playing this game for the story.
Rayman and friends feel great to control, the special challenges and stuff add a lot to the game. You can even play levels originally from Origins, though it's not the same to me...
I think the biggest issues I have with this game is with tone and style, it's just less appealing to me than those of Rayman Origins. Also not a huge fan of the soundtrack, where the previous game had an amazing one in my opinion.

I'd personally reccomend Origins over this one, despite Legends technically having more content. But both Ubiart Rayman games are great.

(my steam review from a year ago)
Overall, I do reccomend this game, BUT only if you really like picross and/or have a huge soft spot for cute robots. (I happen to fit both)
The story is... okay... I have a couple of gripes with it: there's a big issue with tone, someone dies and the characters immediately crack jokes or something; most of the characters are really... flat, some of them are straight up stereotypes; there's also some more questionable choices with writing... but overall I did like it. It's not phenomenal, but it's enjoyable. S.C.O.U.T. is well worth going through the weaker parts of the story <3
Oh also, the story starts out really... slow, it gets better though throughout the cases. The last moments of case 4 felt unsatisfactory, for me at least, though.
As for the gameplay... prepare to do a LOOOT of picross. Every 5 minutes or less you get a new puzzle to solve to progress the story, which is fine by me, because I really like picross, but yeah, there's a lot of it.
Not one of my favourite games, but I liked it. I'd say the strongest part of this game is its visuals. I love the UI and the character designs and the general art style. very cool and pretty.