Obsidian Glaive

The Obsidian Glaive is a weapon used by Ronin and its only appearance was in Shadow of Ronin.

History
There is little to no info about the Obsidian Glaive creation, other than it originaly belonged to Hibiki, and was then stolen by Ronin

Shadow of Ronin
Spoilers

Ronin used the Obsidian Glaive to steal the memories of the ninjas, but Wu stoped him from finishing it.

Ronin would also later use the Obsidian Glaive on the Serpentine, making them work for him.

Ronin later, used the Obsidian Glaive on Misako, making her too work for him, until Lloyd used his powers to destroy the Obsidian Glaive, freeding Misako (and others) from its effect.

Powers
The Obsidian Glaive have the dangerous power to steal and/or alter the memories of its victimes. However, its effect can be reverted by ither ubtaining one of the Obsidian Weapons, or to destroy it.