Kaiu Haru

Kaiu Haru was a Weaponsmith of the Crab Clan and governor of Kotaru Mura.

The Maw's Invasion
The Maw raised an army in 716 the likes of which had not been seen since the days of Fu Leng, and marched upon the Crab. Shortly after Hiruma Castle was conquered, Kotaru Mura was besieged by one of its lieutenants, Chizaro no Oni.

Death
Haru crafted two twin swords, the Blade of Truths and the Blade of Secrets, each tempered with powdered jade, to be used against the Oni. However, even the old master could not fully protect the swords from evil, and each sword was born with a curse, a twist to lead a foolish wielder to destruction. Haru died using the swords to destroy Chizaro, but his sacrifice let the villagers escape.

Aftermath
Since Haru's death, the blades had appeared both in the Shadowlands and Rokugan. Chizaro no Oni's spawn were still particularly vulnerable to the swords, and hunted their owners.