In an alternate universe where Sufficient Velocity focused solely on Genjutsu and the dreaded Bushin no Jutsu…
Daisuke had finally done it. He was but a moments away from the Rookie of the Year position that he could taste it. Well, not really, considering what he was going to achieve the position with.
Bushin. It was all about the Bushin no Jutsu. Since the beginning of the academy he focused on the jutsu in hopes of mastering it beyond its typical limitations, and he's done it, becoming a user so advanced in its uses that he could easily be considered among legends in its usage, a Bushin no Daisuke to the late Shunshin no Shisui.
Daisuke cut through a thousand bushin leaves, punched a thousand bushin dummies, and ran alongside a thousand bushin comrades in arms to get to this exalted position of magnificence. And now will be the test of his skills, to test his very core of his person, or at this point his bushin.
Daisuke walked into the desolate classroom with a air of smugness and little bit of impatience. He spent weeks planning this very day. He subtly influenced his classmates over the course of weeks that there would be no classes today, spreading propaganda and enlisting Ino's help in said matters. He owes Ino quite a bit after all the tasks he had her aid in, for this special moment.
***
Iruka walked into the classroom as per usual, scanning the room to make sure there wasn't anyone skipping before starting class.
… Yep, full room, even Naruto's here! And so he taught the students, who at times bickered among themselves but otherwise paid attention and took notes.
Daisuke smiled happily once this class was coming to an end. He'd cultivated a skill early on in the Academy that allowed him to memorize images and common movements to an extent, though it didn't exactly translate to a skill he could use to memorize things he's read to his disappointment. This allowed him to memorize his classmates general movements and analyze common patterns amongst them that allowed him to simulate a "classroom setting" mode for his bushin replicas of them.
He'd also created his own Genjutsu, his first original jutsu in fact, in order to make a more convincing scene, Yin Release: Sound Manipulation, a D-rank Genjutsu. He'd spent countless hours analyzing his classmates and the noises they'd make whenever they weren't speaking, which allowed him to replica similar sounds throughout the classroom with his mastered Genjutsu.
Iruka turned towards Sakura and pointed at her. "Sakura, what can you tell the class about Konoha's current relationship with Suna?" A pause. Sakura continued writing in her notebook, paying no mind to the teacher's question.
"Sakura? Are you not paying attention to the lesson?" A slight bulge appeared on Iruka's forehead in irritation. … Nothing. No reaction. In fact, nobody was reacting to his annoyance. What was going on?
Suddenly, all of the students simultaneously stared right at him, emotionless, for a few moments before fading away into nothingness. All but one at least.
Daisuke stood up, brushing aside his bushin cloak, rubbing the back of his head with a sheepish smile. "…Well, you see, here's what happened…"
***
And so Daisuke went on to rock the very foundations of the Shinobi World, his mastery of the Bushin no Jutsu unmatched in any capacity. Some say to this very day you can still find lingering bushins walking the streets at nights, remnants of bushins past that Bushin no Daisuke left behind. Some say Daisuke himself became a Bushin after he passed. But what we do know is this…
That Iruka was not at all happy about Daisuke's plan and made him mop the Academy's floors for a month.