From the L5R Discord:
The Itsy Bitsy Spider - 12/11/2018
I remember at the end of the CCG, right before Onyx edition it was revealed that, though they were warring with one another inevery other manner, the Scorpion and Spider had agents work with each other to oppose the Kolat, which makes so much sense.
Both clans were involved in the heavy underbelly and thus would encounter the conspiracies.
Scorpion is the ancestral enemy of the Kolat.
Spider serve the last remaining Hantei, fanatically worshiping his divine bloodline.
In fact, when the Scorpion were given a choice of "Oppose Kanpeki, Serve Kanpeki" they chose to serve Kanpeki to better allow them to purge the empire of Kolat, causing half the scorpion to abandon the clan.
Granted, they turned that into Nitoshi jesus, kind of missing the point of the vote, but still. Scorpion loves killing them kolat.
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The Itsy Bitsy Spider - 02/22/2019
There was a push by scorpion players to "Actually BE the real villains for once, not pretend but actually have the evil ball" and the vote came down to 43% for "Side with the Spider", 43% for "Be ninja sabetures and fight the power" and 4% for some other choice, so the story was supposed to be the Bayushi siding with the Spider, and the Soshi and Shosuro rejecting that choice and fleeing into the shadows, so a Scorpion civil war.
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The following text is from the L5R Wiki:
Bayushi Nitoshi, the Poison Mask, was a member of the Scorpion Clan who lived in the late twelfth, early thirteenth century. He was the Scorpion Clan Champion and was the son of Bayushi Paneki and Bayushi Miyako. Nitoshi, Shoju's soul reincarnated, was born the same year Bayushi Kwanchai redeemed Bayushi Shoju. ...
Nitoshi had been married to Bayushi Kanihime, Bayushi Kwanchai's daughter, and they bore a daughter, which was called Kaiko. ...
During the festivals predating Iweko Seiken's coronation, the Imperial Heir had publicly humiliated Daigotsu Kanpeki by announcing that he would remove him as Spider Clan Champion. Seiken's brother, Iweko Shibatsu would join the Susumu family as their daimyo and become Lord Spider. Kanpeki considered this as betrayal of the deal between his father and Iweko I and declared war on the Empire.
Using the Oni's Eye Nitoshi knew what had been said in the Conclave of Darkness, when the new Dark Oracles had met for first time. They told about a prophecy, a Rise of Jigoku, through the destruction of the Sacred Seals which maintained the barrier between Ningen-do and Jigoku. Nitoshi was aware that a new threaten to the Empire was to come. He ordered to find every scroll that mentioned the Sacred Seals and to leave such secrets only to the Scorpion. Scrolls were taken from the Ikoma Halls, the Miya Records, and from the Mantis Clan. Despite his efforts the First Seal was broken after the Spider Clan claimed the victory in the Battle of the First Seal. The veils between Jigoku and Ningen-do began to thin and a surge of massive beasts in the Sea of Shadows forced the Mantis to be placed on the defensive.
Nitoshi devised a plan, crafting a deception for Kanpeki. The Scorpion Champion beheaded Doji Makoto, and moved to Shiro Shiba where Shiba Tsukimi willingly accepted to be beheaded. At Kyuden Miya he offered to Kanpeki his services, and the services of half of his Clan, proving his allegiance by delivering the heads of the other Clan Champions to him as a gift. Seen as a traitor, most of the Scorpion samurai were destroyed or imprisoned by the Lion Clan. During the fall of Toshi Ranbo Nitoshi and his Clan were instrumental to secure the Iweko family, denying Kanpeki's real target, Iweko II. His wife and son, hostages to the Spider, were got out by Soshi Kitaiko. Kanihime became the new Scorpion leader.