I honestly kind of expected this, but it's still disappointing to see a manga get dropped.
The novel is far superior in my opinion but its also quite different considering a lot of the characters were genderbent in the manga.
(and contains a lot less gags like magical girl warriv )
Outside of this last chapter( and some gags ) the story followed the novel almost perfectly even if manga´s allways leave out some smaller details here and there.
The only somewhat bigger thing that was skipped IIRC was a sub plot about a connection between Ellena and Andariel and a mask that the MC got from Andariel.
But that subplot never really went anywhere as far as i can remember, and was a dropped plot point that only resulted in Elena getting a cool headgear.
I was honestly disappointed that the novel never picked up on this plot point because it was too me a cool mystery.
( i might get some things wrong couse this was over a year ago i read this novel )
In the novel after the MC kills Andariel he gets a vision about her life and gets to communicate with her human spirit ( Andariel in this story used to be a human )
In that vision she gave the MC her face mask that she used to hide her face with and the mask was a really good item for Elena. ( in game it is one of the better items to give to your followers too )
She also tells him about her backstory and also hints that there was a connection between Elena and Andariel.
Both of them shared a title for being the most beautiful and strongest among the rogues, "The Flower of The Rouges".
Apparently everyone who got that title were cursed to a grim fate ( or something like that ) and Andariel asked the MC to try and protect her and keep her from suffering a unfortunate life like she had.
Also if anybody is too lazy to read the 1200+ novel chapters yourself or want to ask some questions about the plot.
Then i can tell you some major spoilers for how this story turns out if you send me a private message.