The Avolakia is a monster from the D&D Third Edition Monster Manual II. It's a ten-foot-tall wormlike aberration with insect legs and octopus tentacles sticking out in a radially symmetric pattern and a mouth that opens up into 3 "flaps" like the sandworms from Dune. Overall, it looks like someone took one of the man-eating worms from the "Tremors" movies and turned it inside-out. Like many Third Edition monsters (see also: Ixitxachitl, Neogi, Unbodied, Glimmerskin) it had a level adjustment and favored class for conversion into a playable race despite being totally unsuitable in every conceivable way for use by player characters.
Avolakias eat undead flesh, which they are able to create with innate necromantic abilities. They serve Kyuss, the Worm That Walks.
See also: Dungeons & Dragons 3rd Edition races