Armored Lituslug
The armored lituslug resulted from a population of lituslugs that migrated into the abyssal zone. This new population tended to frequent around banded iron formations near the vents. These lituslugs often had large quantities of sulfur accumulate inside of them. In order to eliminate the waste sulfur, they developed a series of organs that excrete sulfur on its back. Because of their high iron content, this sulfur often reacted with the iron to form a pyrite shell. This shell grows constantly but is kept in check by the surrounding water, which slowly decomposes the outermost layer of the shell. This shell also helped protect the mutant lituslug population from the heat produced by vents, though the effect of this insulation is limited. These lituslugs also developed a row of eyespots to help them detect the dim glow of lava flows, which they will attempt to avoid.