OD&D v2: Monsters & Treasure

Much of the Chainmail fantasy supplement was incorporated into the OD&D rules.  Some of the material is verbatim, while other parts were expanded upon.  Additional sections were derived from Dave Arneson's Blackmoor campaign.

D&D volume 2: Monsters & Treasure (Jan 1974)

The second volume covers monster descriptions (with a reference table), treasure types, explanations of magic items (including "super swords"), saving throws, a short description of artifacts, and treasure (precious metals, gems, and jewelry).

Most of the monsters appeared previously in Chainmail.  Some categories were expanded - such as men (bandits, berserkers, brigands, dervishes, nomads; buccaneers, pirates; cavemen; mermen), giants (hill, stone, frost, fire, cloud), and sprites (nixies, pixies, dryads).

Hobgoblins and gnolls are added, the latter described as "a cross between gnomes and trolls (...perhaps, Lord Dunsany did not really make it all that clear)"

The creature described as the gnole first appeared in 1912, in Lord Dunsany's story "How Nuth Would Have Practised His Art upon the Gnoles", and reappeared in Margaret St. Clair's "The Man Who Sold Rope to the Gnoles".

Lord Dunsany's story gives little or nothing in the way of physical description of the gnoles, but they live on the edge of a sinister wood and watch intruders through holes bored in trees.  They are said to own emeralds of very large size.  In St. Clair's story, they also live on the edge of a wood, watch through holes bored in trees and prize emeralds, but a "senior gnole" is described as looking "like a Jerusalem artichoke" and, although he has feet, has tentacles rather than arms and no ears.  His eyes are small, red and faceted like a gemstone.

from the Wikipedia entry for "Gnoll"

Gygax later stated "The original gnoll was a strange critter in a (rather bad) novel that I wrote and was in part run in Dragon magazine's early numbers.  I didn't find that creature a suitable humanoid for the D&D game, so I revised gnoll into a hyena-like humanoid.  (I find hyenas most unappealing in all respects, including their stench)" in a forum post, here.

In 2014, Jon Peterson postulated that some of the additional monsters in Monsters & Treasure, such as the gorgon, might have originated from Ernst and Johanna Lehner's "A Fantastic Bestiary: Beasts and Monsters in Myth and Folklore" (1969).

"A Fantastic Bestiary" also includes entries for the "manticora" (note the spelling), and a section on "benign" monsters, including the centaur, the pegasus, and the unicorn (the monster reference table in Monsters & Treasure is subtitled "hostile and benign creatures").

Two additional creatures from Greek mythology were included, classified as a type of monster in D&D thereafter, namely Medusa and the Minotaur.

Jason fighting the Hydra, movie still from wikimedia commons

The dinosaur-like hydra was likely inspired by Ray Harryhausen's version from Jason and the Argonauts (1963), which also included skeletons.

Additional undead not appearing in Chainmail were the mummy and the vampire, likely based on Hammer Film Productions The Mummy (1959) and Dracula (1958) respectively, although vampires were already present in Blackmoor, inspired by the Dark Shadows TV show.

The gargoyle from French legend, as depicted in medieval architecture, is a creature not appearing in the Lehners' "A Fantastic Bestiary".

Finally, the so-called "Dungeon Clean-Up Crew" (ochre jelly, black (or gray) pudding, green slime, gray ooze, yellow mold, and the gelatinous cube) are unique to D&D, although inspired by monster films (ie. "The Blob", "The Green Slime").

Excerpt from Chainmail (1971), including mention of Excalibur and other "Super Swords"

In the treasure section, there are extensive rules for magic swords.  King Arthur's "Excalibur" and Elric's "Stormbringer" are clear inspirations.

Daniel Boggs explains the source of these rules, from Arneson's Blackmoor campaign, in his 2012 post Tracing Magic Swords.