Volo's monster lore section is just great – nice balance of lore, cool concepts to hang adventures on, supporting tables, and mini-lairs/maps.
I'm strongly looking at Nord Games'
Revenge of the Horde as my next monster book purchase (
review link); seems like they took a VGtM kind of approach to bugbears, gnolls, goblins, hobgoblins, kobolds, orcs, and trolls.
EDIT: Oh! I remember there was a joke about
Volo's Guide to Specters & Spirits, but just saw that Nord Games also put out
Dreaded Accursed covering ghosts, ghouls/ghasts, lycanthropes, mongrelfolk, mummies, revenants, shadows, skeletons, specters, vampires, wights, will-o-wisps, wraiths, and zombies!