I'll keep this as spoiler free as possible.
Coming off the first game, expectations for the continuation to Digital Devil Saga were sky high, specially with all the build up done in the first game, and not only does this game deliver how it was promissed, it goes above and beyond to make it even better than expected.
So, lets get the things that are about the same first.
Gameplay remains the same, with the big change being the mantra grid being way more open as it follows a non linear structure to get skills, which imo, its better as it gives even more freedom, with the possibility to jump from 2° tier skill after following a line, into another one on the fly.
Dungeon design is as stellar as always, the OST is the best one of any game still, and it looks and animates beautifully.
Now, for the writing.
OMFG, EVERYONE IS INCREDIBLE.
The development they gave to Heat elevates him a lot more than how great he was, and the twists involving him, Sera and Serph are absolutely world shattering crazy.
Gale gets even more development and gets turned into a character that can genuinely be considered the best written one in all of MegaTen, Sera finally gets explained fully, and becomes incredible, Cielo and Argilla get scenes that show how amazing they are, we even get a new party member in Roland, who despite being for only 1 game, becomes an amazing character who can stand alongside the rest too, and Serph, I have never been too fond of silent protags in RPGs, but omfg, they even managed to make the SILENT MC incredible here. And the main antagonist in Angel becomes my favorite antagonist ever, in just how threatening and evil she is, as well as how you can sympathize on how she got there, and what exactly caused it.
All tied to a story that goes every single place possible, and manages to leave such an impact it feels unbelievable so many times, specially with how emotional it gets, I cried dozens of times to this game, specially on one ocation where I cried for 15 goddamn minutes.
This duology is a masterpiece, and this is the biggest payoff to everything that was built up, and was done beautifully.
It came at a trying period of my life, and helped me find comfort in regards to trauma I suffered months prior to playing it, it is easily my favorite work of art ever, and something I recomend to everyone.
Give it a try if you have even the slightest curiosity on it, you won't regret it.

THE POWER IS YET UNKNOWN! THE POWER IS YET UNKNOWN! THE POWER IS YET UNKNOWN! THE POWER IS YET UNKNOWN! THE POWER IS YET UNKNOWN! THE POWER IS YET UNKNOWN!
This game has a lot of style and is dripping with soul, pushing the DS's capabilities.

Gameplay Rating: 8/10
It's an incredibly unique game with how you control it. The application of the touch controls works pretty damn well with relatively little issue. The game really tests your mettle with having to control both Neku and his partner at once.
That said, the game is INCREDIBLY rough on the hands. I could barely play for more than 2 hours at a time due to how bad it made my hands ache.

Story Rating: 10/10
I don't want to get into much here because TWEWY is best played unspoiled, but I'll be vague here.
At first, I didn't understand why Neku liked his second partner after the end of Week 2, but then it kind of hit me. The message that the game continued to spell out finally clicked.
"Everyone has their own little internal world - a secret garden only they can enter. Each world follows its own internal logic - individuality. And the logic of one world means nothing in another. Understanding other people isn't hard.....It's Impossible."
The moment I realized this, this game went from good to fantastic. I don't think I people were meant to understand Neku, and that was perfectly ok.

Colorblind Rating: A
I don't believe there were any issues regarding color in TWEWY, which is surprising given how vibrant everything is.