Written by Jonathan Wojcik
Introduced in the original Fiend Folio, the Meenlock is a hairy, spiny, nasty little bug-faced gremlin whose habits sound straight out of a child's nightmares; living at the bottom of deep, well-like shafts, Meenlock will "mark" you for disturbing the entrance to their lair, stalking you from the shadows and sending telepathic threats that they're coming for you, and soon enough, you'll become one of them. Nobody else sees them or hears them. Nobody else believes your paranoid obsession with the mysterious entities you know are pursuing you. You're completely on your own until they finally jump you in your sleep, drag you away and transform you into another Meenlock by unspecified but supposedly torturous means. This guy probably has it right that the monsters are a reference to the original Don't be Afraid of the Dark, where more or less the exact same thing happens.
Meenlock have survived well into recent editions of the game, and are fortunate enough to have remained pretty cool throughout their portrayals. This second edition Meenlock is pretty damn awesome with its huge eyes and gnarly talons. Like the older Ettercap, it resembles an arthropod without actually being an arthropod at all. The method of transformation from humanoid to Meenlock was now said to involve the application of special type of moss found only in Meenlock lairs, which is interesting.
Now sporting large, chitinous pincers, the 3rd edition Meenlock artwork is probably my favorite, nicely illustrating a high level of variability in their transformations. The foreground specimen appears to have been a woman at one point, her monstrous new form bearing spider-like chelicerae. The background Meenlock is even cooler, with his bulging eyeballs and mean little teeth. I love the fly-like hairiness of these Meenlock, and their sickly shades of pale green and yellow. They look an awful lot like anthropomorphic lice, which is delightful in every way.
The most recent Meenlock fortunately doesn't stray too far from the previous edition. Squatter and darker, it gives off a slightly more crab-like impression and has the sort of gnarled anatomy I've always loved to draw myself. Oddly, though every single iteration of the Meenlock has some arthropod-like features, no relation to insects, arachnids or crustaceans has ever been noted in their associated text.
I always thought that if I could play any monster at all in a D&D game, I might actually go for for a not-so-evil Meenlock, maybe someone who got off only partially transformed by their mysterious rituals. Meenlock are that perfect combination of ghoulish humanoid and alien bug that appeals to me the most - I'd have loved these guys to have an official miniature I could own.