Really, actually, seriously gets rid of the Grendel/Ettin spawning machines and all currently existing eggs. (Emphasis because some older cobs floating around only do one or the other, not both!)
Grendel/Ettin machine remover
Removes the Grendel and Ettin egg layers and associated scripts.
0 Grendel Egg-Layer Remover
Removes the Grendel egg-layer and destroys all existing Grendel eggs.
0 Ettin Egg-Layer Remover
Removes the Ettin egg-layer and destroys all existing Ettin eggs.