Pestilens Clan Virulox made the very unfortunate decision of picking a fight with fellow Pestilens Clan Septik. Their squabble soon became a miniature civil war dubbed the Buboe Wars. Virulox made deals with Skryre Clan Phrikk to develop new and more powerful plague engines and waged war alongside their many thrall clans. They and Septik went at it like rabid... well rats, filling the labyrinths of Pyropia with their bodies, as well as the Moonclan lairs nearby.
It is unclear who won this fight, but since this was Virulox’s only mention, it can be assumed the results weren’t kind to them.