Just trying to gather the threads together in one place.
So, to date in the fiction we've had 2 (separate?) visions of trouble on the horizon. First, from 'The Rising Wave', Togashi Yokuni sees a great wave (like a scorpion’s tail) that devastates Otosan Uchi, leaving it a barren wasteland, which is where the Empire must subsequently confront its enemy(ies?) for there to be any hope of victory.
Second, Isawa Atsuko in Smokeless Fire sees a samurai in purple + fur, a carven antler flashing silver, a cracking ruby between 2 gold wings, an eclipse, then a shadowy figure emerging and striding blood-soaked earth to the Imperial Palace.
Kaede sees that the ruby surrounded by gold wings is a meishodo amulet that contains the shadowy figure, trying to break free & reach the Emperor.
As a result, Iuchi Shahai, noted student of meishodo, is sent to the Imperial Palace where she meets the younger prince who may or may not be learning dangerous lessons in perception vs reality.
While hunting with her family, Shinjo Haruko kills a deer and Yasamura suggests carving the antlers into hilts for daggers, and Shinjo Altansarnai insists on an extra dagger for Shahai. Notably, Altansarnai's children are uncomfortable at even the mention of their half-sibling's name.
Meanwhile, Bayushi Kachiko is of the opinion that the Emperor Hantei XXXVIII has lost the favour of the heavens and (worse?) has stopped doing what she tells him to do.
Wild supposition: The 2 visions are related. Cracking open the meishodo amulet & liberating the spirit inside is what causes the devastation to Otosan Uchi that Yokuni sees. The Scorpion are at fault, insofar as Kachiko's machinations will create an opening for Hantei Daisetsu & Iuchi Shahai to try to eliminate his father & older brother in one fell swoop. So, there's still a 'Scorpion Clan Coup' of sorts, except it's to put a different Hantei on the Throne.