I don't recall when or where I first heard of it, but when I did hear there was a book out called Wynonna Earp: The Yeti Wars, I quickly put it on my "should get" list. I mean, Yeti Wars! C'mon! That has awesome written all over it! But that turned out to be the biggest problem with the book: the title just set my expectations far too high.
The story features U.S. Marshal Wynonna Earp and a small band of elite specialists who focus their energies on stopping the more paranormal problems in the country. In Yeti Wars the Immortalis Consortium have hired a brilliant, but psychotic, geneticist to help set the stage for a race war with the Vampire Nation. Humans, of course, are inconsequential to the feud, but would inevitably be caught in the crossfire. So Earp is charged with stopping this geneticist, who's creating his own ersatz island of Dr. Moreau full of synthesized monsters for the vampires.
Or something like that. Honestly, despite a couple of pages of plot exposition early on, it was actually a bit unclear who this geneticist was working for and what exactly he was doing for them. He very clearly did make a bunch of monsters, but we're not told why. And, after his first lab is blown up, he doesn't do anything else along the same lines. He's in a lab and looks at samples of stuff, and speaks in a kind of unorthodox manner (to show he's almost, but not quite, unhinged) but what he's actually doing... I'm not sure. It doesn't help, too, that he's apparently trying to double-cross the vampires, so his actions are always suspect.
As for Earp and her team, there's not much to say. They're pretty flat characters for the most part. There's some banter among them, and a grudgingly respectful rivalry between two of the lesser characters that's covered in sarcastic comments. But not really anything by way of character. I didn't see any evidence of motivation beyond the "it's my job" variety, and their lives outside of work were non-existent aside from a few snarky jokes about sexual activities.
You notice I haven't said anything about the Yetis yet? That's because they're actually pretty incidental to the story. They're guards for one of the labs. And then Earp brings in a freelancer who has a few Bigfoot at his disposal. It's not so much a series of Yeti Wars then as it is a single Yeti/Bigfoot skirmish.
The story isn't bad, really. It flows well enough and progresses along fairly smoothly. The plot doesn't have any serious flaws, I don't think; there was just so little characterization that it all fell a bit flat. I didn't connect with the characters at all and, thus, didn't really feel engaged at any point. It just sat kind of sat there. Especially in lieu of the expectations that the title set up for me. And that's one I blame on myself; I definitely should have realized before getting it that there was almost no way it could live up to what I had in my head.