The eye of stone is a particularly rare terror that occurs after a beholder has encountered both a gorgon and a roper, and their nightmares merge the two into itself, creating a creature that, when at rest, resembles nothing more than a large boulder or outcropping, and has the abilities of all of its component creatures.

Like all beholders, they believe themselves to be the pinnacle of creation, and fear and hate all things that are different, so usually they swiftly destroy their beholder parent and seize their lair.

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