C is for Carrion Crawler
Carrion Crawlers are large (3′ to 4′ long) pale yellow and greenish creatures similar in appearance to a centipede. Crawlers possess eight long tentacles protruding from the sides of their heads, allowing them to stun prey. Carrion Crawlers scavenge the dead and occasionally prey on living creatures.
The OD&D Greyhawk supplement Carrion Crawler reminds me more of Sponge Bob than a threatening monster, but it got nastier in appearance as it got older.
I kind of like the “cute” Carrion Crawler best. It seems more devious to me as a GM to have this happy looking guy munching on PCs rather than the predictably ravenous looking later versions.
This critter is one of the most infamous of D&D foes. A good dungeon adventure, old grave yard or other suitable place where they would live make great places to encounter Carrion Crawlers. Having hundreds of newly hatched ones swarm PCs (say, in a pit trap or hallway) is one way to keep this creature formidable, even to higher level characters.