Harpy Thyme - This time, it's the Magician Trent whose youth is restored, but the main character in the book is the goblin-harpy cross-breed Gloha. Overall, it's a pretty standard Xanth adventure, with another character seeking an appropriate spouse, and encountering a lot of pun-filled adventures on the way. There are a few odd twists, though, like a giant suffering from bone marrow cancer. Fortunately, this being Xanth, there's a magical way of healing him, and a happy ending in store. I do have to wonder why the characters have such trouble finding a trans-plant, though, when you'd think Trent would just be able to transform something else into one. We also see the Demoness Metria, a succubus with vocabulary problems who helps or hinders mortals whenever she finds it interesting, finally settle down into married life.
Geis of the Gargoyle - Not all of Metria's demonic mind is satisfied with this arrangement, however, so her alternate personality Mentia splits off and has adventures of her own with a water-purifying gargoyle named Gary and the youthened Sorceress Iris. The story is pretty odd even for Xanth, in that most of it takes place in the ruined city of Hinge in the Region of Madness, and involves the main characters playing roles in an illusory reenactment of ancient Xanthian history. According to the author's note, one of the main points of this excursion is to resolve some contradictions in the series, sort of like Thief of Time did for Discworld.
Roc and a Hard Place - Speaking of restoring old characters, this one includes characters from nearly every previous book, and ties up a fair number of loose ends. The main character this time is Metria (with her alternate personality Mentia once again attached), who is ordered by the Simurgh to summon others to take part in a trial. During the course of this adventure, several characters get hitched (I'm not sure it's possible for any Xanthian NOT to end up marrying and having children, which allows for some interesting matches, but also gets a bit repetitive after a while), the curse on Threnody is broken, we learn the significance of Che Centaur and the egg being hatched by Roxanne Roc, and such characters as Arnolde Centaur and Ichabod the Archivist make their first major appearances in some time. Like Question Quest, in addition to being an interesting story on its own terms, it also provides a good overview of the series so far. Seeing the trial itself was also interesting, although I doubt most court cases in Xanth work out that way. I think it occasionally suffers from trying to cram in too much, though. For instance, while I found the Book of Kings fascinating, its appearance had nothing to do with the plot, and should probably have been saved for a later book. Still, this was probably my favorite Xanth book since Question Quest.
I've read the first chapter of the next book (at the time I originally wrote this, anyway; I've read considerably more of it since), Yon Ill Wind, so expect a review of that one sometime soon. Not that anyone cares, most likely, but I'm sure I'll keep writing them anyway.