Anomalies originating from radioactive bomb craters generate such monstrosities that pre-war scientists would never imagine! Mephisto is a monstrous worm, a unique synthesis of flesh and steel, which can be a serious threat to even well-armed forces. Contaminated crater - Mephisto's territory - is a tempting shortcut route and a source of resources, but, too often, it becomes a graveyard for newcomers!