The creature is very similar to the smaller Arachnotrons, right down to the cybernetic leg replacements. This has led to speculation of a relation, specifically that these creatures may be the females of their species, with the Arachnotrons being their offspring. While this has never been confirmed in action, it remains a logical hypothesis.
The Spider Mastermind Edit
When talked of as a particular entity, "the Spider Mastermind" refers to the demonic entity that existed in the Dis region of Hell. This being is believed to have coordinated the invasions of the two Martian satellites, Phobos and Deimos. Next to the Icon of Sin, it is the single most powerful demon recorded in the hierarchy of Hell.