Perdition is a great book for LitRPG. It's the third book in a great _series_ for LitRPG.
To be fair, it violates a lot of LitRPG tropes. It has a _female_ MC, the MC is not only _female_ but is a lesbian, she's not only a lesbian but she's a _healer_, she's not only a lesbian healer but the lesbian aspect doesn't veer into harem - she's monogamous - and she's not only a monogamous lesbian healer but she's not even overpowered!
And the story itself goes into why someone might choose to be one of the "bad guys," to the point where you start to question whether the "bad guys" are even the actual "bad guys," as opposed to being the primary antagonists in the service of _other_ stories.
It's written in a humane, funny, appealing style - you'll groan your way through some of the jokes (and follow up by grinning at them), you'll giggle your way through homages to other games, you'll fully recognize the MMORPG chops of the author - and if you're wise, like I hope I am, you might even change how you look at RPGs.
The strategy and the writing is _that good_.
But wait - there's more.
In Perdition, the third book, the author introduced a new character, what I think is a groundbreaking character for me. I can't say there's been no other such role in LitRPG - I don't have that kind of exhaustive knowledge - but I can say I know of no other author who's gone in this direction.
There's a person who is insane, and not in the A-Team's "Murdock is crazy, ha ha" sense, but clinically mentally ill, with schizophrenia and epilepsy in the life he had before he entered the VGO game world. He's not even sure which world was "real" - neither was consistent, neither made sense to him, neither one looks to him like it would to anyone else. He's constantly hallucinating, constantly warping in and out of what is and what should be.
And the effects of that warping are portrayed realistically, in the context of the series. It's got humor to it, because life is funny, but it's also tragic to read, and when you factor in the author's actual awareness of such illnesses... it ends up causing an emotion on the part of the reader that serves as an accurate gauge of who the reader _actually is_.
The MC even tries to address it; it's fiction, and it's in a game world, so who can say what the "real outcome" would be, but it serves to demonstrate a humanity that's largely missing in the genre. And that it's not played for laughs - even though laughter is present - only makes it more poignant.
And then the story continues as it should around him - an outcome that will break your heart - and in the end, he is left broken, but in a way that ends up being incredibly uplifting despite its essential sadness and cost.
I can't say Heartfire is for everyone. But I can say that in all of LitRPG, with all of the joy I have managed to find in the genre, Heartfire is probably the best actual literary achievement I've found, and the series I'm most glad to have been able to read.