Finally, the Purple, or Mottled, Dragon is a rare, flightless worm with a venomous sting in its tail.No other details are given for this Purple Dragon. Of course, Volume 2 of OD&D, which contains the illustration accompanying this post, provides the first write-up of this creature, under the name by which it became staple of the game.
These huge and hungry monsters lurk nearly everywhere just beneath the surface of the land. Some reach a length of 50 feet and a girth of nearly 10 feet diameter. There is a poisonous sting at its tail, but its mouth is its most fearsome weapon, for it is so large as to be able to swallow up to ogre-sized opponents in one gulp.Other than its color, the main element that carried over from Chainmail is the worm's poisonous sting. Interestingly, the AD&D Monster Manual includes an aquatic variant of this creature, called the mottled worm, which recalls its first appearance in Chainmail.
I'm a big fan of re-imagining classic monsters in ways that aren't arbitrary but rather reflective of their complex histories/origins. The purple worm, which I've yet to have any reason to use in my Dwimmermount campaign so far, strikes me as a good candidate for such a re-imagining. While I've avoided detailing any more of the campaign setting than I need for my immediate purposes, I have to admit that I have been giving some thought to the role of dragons, if only because it seems a shame, in a game called Dungeons & Dragons, not to use these creatures at some point. So, the thought has crossed my mind that purple worms (purple wyrms?) are in fact related to dragons, if not actually a subspecies of them. That'd necessitate making them less worm-like and more reptilian in appearance, but that's still in line with OD&D's general description of them, while also being an homage to Chainmail.
I like that.