D&D Monsters: Dryads

Looking again at D&D creatures derived from Greek myth, we come to the dryad. In the original myths, dryads are a type of nymph, or female nature spirit, associated with trees. Originally, the tree specifically had to be an oak tree, but later on the term seems to have been used more broadly for woodland spirits in general. The term "hamadryad" was used for a dryad so closely bonded to her tree ("hama" means "together") that she would die if it did, but others seemingly had no such vulnerability. So far as one can tell, they were supposed to look like regular human women.

Dryads have occasionally appeared in works of fantasy fiction, most notably in C.S. Lewis' Narnia books, which maintains the distinction from hamadryads. In D&D, dryads and nymphs are different kinds of being, albeit with a number of similarities, but the latter did not make it into the 5E Monster Manual, something that's currently one of my criteria for including something in this series. In the first few editions they are, however, said to be "tree sprites"... but it's not clear what this means, since a sprite is yet another distinct creature in D&D, and one that resembles dryads rather less than nymphs do.

D&D Monsters: Zombies and Skeletons

As I have noted previously, undead in D&D represent at least three different broad categories of being: mindless corporeal, sentient corporeal, and noncorporeal undead. Zombies and skeletons fall into the first of these three categories, distinguished by the fact that they have no will of their own and are effectively automata under the control of their creator. They are also the weakest form of undead, a problem only for low-level characters.

It's well-known that zombies have their origin in Haitian legends, perhaps influenced by older African legends, but probably having more to do with the experience of slavery. In these legends, a recently-dead corpse is re-animated by an evil sorcerer, which it then serves as a mindless slave lacking all free will. The modern conception of the zombie, however, originates with George Romero's 1968 film Night of the Living Dead. Ironically, that film never actually uses the word "zombie", but it has become widely used since to refer to a selection of similar beings in films and other media.