The ovipositor, giant egg-sac or simply the Queen's butt, is a giant Insectoid egg-producing organ on the rear end of Queen Slug-for-a-Butt. It resembles the ovipositor of a queen termite, and is the source of all life on Insectika. The monarch of Insectika gained her unusual moniker from her giant reproductive organ.
In Buttville, the final level of the original Earthworm Jim video game, the Queen's ovipositor plays a major role. Jim has to land on a portion of it before he falls into a canyon of spikes. Jim then fights the mini-boss of the level, J. Alfred Maggot, which is actually the rear end of the ovipositor, the egg-laying part. Jim then proceeds under the ovipositor towards the Queen at the front of the ovipositor, which becomes a main enemy in itself, trying to ooze corrosive acid on Jim. The ovipositor also spews out Insectoid Hives before Jim's final battle.
The Queen's ovipositor has changed in appearance in various sources. In the Earthworm Jim video games, comics and toy line, the Queen's ovipositor was depicted as being hundreds of feet long, but in the animated television series, it was only a dozen feet or so long. This may have been for practical purposes, or it may have been intentional, with the cartoon being a prequel to the games.
- Ovipositor article on Wikipedia