The promotion to Chunin gave Aizen the one thing he craved most: Autonomy. No longer tethered to a three-man squad or constant supervision, he began to weave his web through the very foundation of Konoha's power structures.
His first target was not the Hokage, but the Uchiha Police Force. Following his victory over Shisui, a fracture had formed within the clan. Some feared him, but others—the younger, more ambitious members—were drawn to his "absolute" power. Aizen began holding private "philosophy sessions" in the woods, disguised as advanced Genjutsu training.
Among them was Fugaku Uchiha. Though he was older, Fugaku found himself seeking Aizen's counsel on the growing tension between the clan and the village elders.
"The elders don't trust the eyes that see too much," Aizen told Fugaku one evening, their shadows stretched long by a small, contained fire. "They give you the 'Police' title to keep you busy, but they deny you the 'Hokage' seat to keep you contained. It is a slow suffocation, Fugaku-san."
"And what would you have us do, Sosuke?" Fugaku asked, his voice heavy with the weight of leadership.
Aizen adjusted his glasses, the firelight dancing in the violet depths of his eyes. "Don't fight for a seat in their world. Build a world where they have no choice but to beg for a seat in yours. I have discovered... a way to evolve the Sharingan. A way to bypass the tragedy of the Mangekyo."
Fugaku's heart skipped. "Is such a thing possible?"
"With my assistance," Aizen whispered, "nothing is impossible."
While Aizen manipulated the Uchiha, he also maintained his "loyal friend" persona with Minato. He knew Minato was watching him, reporting his every move to the Third Hokage. Aizen allowed this. He fed Minato "secrets" that were actually decoys—minor forbidden jutsus and harmless experiments—to keep them occupied while the Hogyoku reached its second stage of awakening.
The Order of the Void: The First Recruitment
Aizen didn't want a village; he wanted an Espada. In the dark corners of the Land of Fire, he began recruiting the "broken" shinobis.
His first true follower was a young, disillusioned Jonin named Kaname (a different version of Tosen in this world, perhaps a blind monk from a fallen temple).
"Why do you follow me, Kaname?" Aizen asked him in their secret lair.
"Because you are the only one who speaks of a world without the 'Will of Fire'—a flame that only creates shadows," Kaname replied.
"Then let us snuff out the candle," Aizen said.
By the time the Third Shinobi World War was beginning to brew on the horizon, Aizen had already compromised three of the major clans and had a direct line into Orochimaru's most secret research. He was no longer a student. He was the architect of a new reality.