An Unwelcome Quest - Scott  Meyer
On this dry, stony outcropping, there was a castle so Gothic it might as well have been wearing black eyeliner.
Beneath the shadow of that Phillip and three of his friends/fellow wizards have learned that they're part of a real life video game, with real life stakes.
How'd they get there?  Well, one of the first things that every wizard is told when they come back to Medieval England is that if they become a threat to the wizards way of life, they'll be stripped of their powers and returned to their own time. In Spell or High Water, we saw one wizard find a work-around for that.  Turns out, he inspired another one, Todd, to do the same. Todd's careful, and he bides his time before revealing to anyone he's come back so that he can cook up an elaborate revenge scheme against those that he primarily blames for his exile. They have to survive a lethal video game for a chance to battle Todd face to face.
Since Todd was sent away before Martin and Roy arrived, Todd ignored them, leaving Marvin free to go grab Brit (the Younger) and Gwen to help.  Their experience in the game is a little different than the others' -- for one, Todd doesn't realize they're there, so what happens to them is just part of the program, there's no interaction between Todd and them, so there's no obstacles or challenges designed with them in mind.
Once the setup was explained, I figured there'd be a lot of satire of video games, or this would end up being a parody of some.  Not at all -- sure, this isn't a particularly well-designed game, so there's some critiquing of the game, but that's about it. Meyer finds his humor elsewhere (phew!). Mostly, the game is pretty easy -- sure, there's some disgusting bits, some dangerous parts, but on the whole, the "players" spend a whole lot of time without much peril. Parts of the experience were almost nice:
The men also agreed that the woods were quite nice and that hiking through them might be rather pleasant if they had a choice, but they did not. Unfortunately, human nature dictated that anything, no matter how pleasant it is, can become hateful if you feel you must do it. Just ask anyone who’s ever entered a pie-eating contest.
As is the norm by now, this book is filled with Meyer's particular brand of humor -- some word play, some situational humor, some sarcasm, some character-driven humor.  There's some friendship, some romance, a little villainy, and some stupid pranks. All told in a charming, engaging way.
I do think it's time for this series to end, but I'm going to miss these characters and their banter, this world. This book made me laugh out loud, which I don't do often enough while reading. I'm pretty sure this was the first time I've chuckled at a waterboarding joke (don't worry, it's not offensive in context -- really) -- any book that can pull off that feat is worth a read.
Seeing that on the screen, that last sentence seems to be damning with faint and objectionable praise -- really, it sounded good in my head.