Obsidian glass

Obsidian glass is a naturally occurring rare volcanic mineral formed as an extrusive igneous rock.

During the fifth century BCE, the Cyclops of Kephallonia had a prosthetic eye made of obsidian glass. The Spartan misthios Kassandra infiltrated Cyclops' lair and stole the eye on the advice of Markos.

During the Peloponnesian War, Kassandra gathered obsidian glass and used it to better her gear.

Appearance

 * Assassin's Creed: Odyssey