The Beholdroid

The Beholdroid was a beholder who was abducted and experimented on by the Ytarans at Polaron in an attempt to farm eldritch eyes by increasing the size of the eyestalk eyes such that they'd be useable as eldritch eyes.
They succeeded, but then died off from the Astral Plague, leaving the Beholdroid to stew for centuries until the party arrived. Epsilon convinced him to attempt to kill them (and also whipped up some anti-Dwarf sentiment), but the party won the battle. Now they don't have to worry about eldritch eyes anymore.