Harvester

Beings who apparently have a vital role in harvesting the protein from captives to feed The Sphere. They come in two varieties, one which walks around on mechanical legs (which can be blown off) and can travel freely through a network of organic tunnels, and one which has attached an antigravity device to itself, allowing it to fly through the air freely. Both kinds of Harvesters are armed with Crawler Launcher, but only the walking variety use the alternate fire.

Trivia

 * Flying harvester version has been said to bear resemblance to the Assault Commanders from Duke Nukem 3D