It's reasonably good, but not special. I'd watch a second season, but I don't know if I'd recommend it.
It's set in a fantasy world that's clearly based on the 19th century USA. Superpowered beasts called incarnates were used by the North to win their civil war with the South. They're almost unstoppable. The only thing that can reliably kill an incarnate is another incarnate. Unfortunately, after the war, they're losing the last of their humanity and are becoming a threat to the society that created them.
There's an incarnate, Hank, who's hunting down his former subordinates and telling himself that it's for their own good. There's a girl, Nancy Schaal Bancroft, who doesn't have a problem with the fact that her father's now a dragon as big as a church and can no longer turn human again, or even speak.
After a highly dramatic opening, the series settles down into an "Incarnate of the Week" formula. I'd have been fine with that, since it actually provides some of the show's strongest episodes. Behemoth in ep.4, for instance, which is pretty horrible. Halfway, though, the show grows a storyline. That's also pretty good, although it's based on a dark fantasy manga that's still ongoing and so the anime's story doesn't end here. It just finds a good place to stop, complete with a tease for a Season 2 that may or may not happen.
There are various levels on which one can discuss this.
1. THEMES AND MESSAGE
The show's talking about PTSD and war veterans being left to rot. The incarnates get no emotional or practical support, despite strong evidence that their psychological state is what determines their permanent shift into monsterdom. (It's the incarnates with a strong sense of purpose who best retain their identities, even if their chosen purpose happens to be evil.) On the contrary, the government wants them killed and has death squads.
This theme doesn't quite fit the show's mildly cliched plot choices, but that clash is interesting in itself. The male protagonist, Hank, is a walking pit of despair who thinks his kind have no future and need killing. He sees himself as a dead man walking. I had much more sympathy with the arguments of the stereotypical ham villain who says things like "you have outlived your usefulness". He's absolutely right about how the humans have treated his people, he has positive goals and he's giving purpose and psychological support to his fellow monsters. Look at the North's human government's actions, e.g. ordering the extermination of all incarnates because it'll play well politically, even when threatened by a warlike rival state with lots of incarnates. D'oh. Too dumb to live.
Personally, I think Cain has the right idea and the best outcome would be for him to succeed in his war... but we're meant to be booing him, because he's so luridly being painted as the baddie.
More fundamentally, it seems that the bleak, depressing point of view is correct. The PTSD-aware viewpoint being championed by Schaal is undercut by the apparent fact that these people really will degenerate into monsters with mass-murdering superpowers and no interest in self-control. I hope that gets subverted... but in fairness that process has already started. Trice in ep.8 isn't dangerous. Her power just induces sleep.
2. SETTING AND AESTHETIC CHOICES
I like the 19th century pseudo-USA setting. It's unusual in anime and creates plenty of colour. However...
(a) Liza Renecastle's character design is stupid. Did we need a mega-boob exhibitionist who's in the military and yet dresses like a stripper?
(b) the Coup de Grace unit have jetpacks, super-guns and night vision goggles. In the 19th century. Yeah, right. I suppose you could argue that anything goes in a world of incarnates, but their equipment in the original manga isn't anachronistic.
(c) I got the vague impression that the process of creating incarnates was medical and scientific... but I couldn't buy this with Cain the Incarnate Vampire. He's supernatural. Or maybe magical.
3. THE CHARACTERS
This is what I was watching for, really. Schaal represents compassion, questions bloodthirsty assumptions and has sympathy for the monsters. Hank has issues. Both of them grow significantly over the course of the series. Even someone like Claude turns out to be less one-dimensional than his plot role would suggest.
Oh, and it seems clear to me from ep.12 that a certain character is in love with Hank. His berserk button, twice, was seeing a woman stroking Hank's face.
This isn't a first-rank show. I probably won't keep the episodes. There's some interesting content here, but there's only one regular character I connected with (Schaal). The others are either too macho-stoic (Hank) or defined by their plot roles and/or bust sizes, although I like some of the one-off characters in "incarnate of the week" episodes.
That said, though, I like the world, the dynamic plotting and the show's basic concept. It's travelling in what could be interesting directions. I wouldn't mind seeing another season.