When up against a monster like Shoto Todoroki, one can't simply waltz in and expect to win, no matter how powerful you were. Izuku was damn well aware of that.
When formulating the plan for said opponent, he knew that he had to capitalize on the biggest advantage he'd ever hope to have.
Unbridled speed.
It obviously wasn't All Might's speed, although coupled with Toxin and 25% of OFA, he wasn't too far off. Regardless, it was plenty enough to be faster than an unenhanced human should be able to track with the naked eye.
The plan involved using this speed to evade the ice. It would be hard to get a clear shot, due to the AOE nature of the ice, but there would be enough room for him to improvise at least that part of it until the next step would be necessary.
"COMING UP FOR THE FIRST ROUND OF THE QUARTER FINALS, IS THE UNDEFEATED, TERRIFYING IZUKU MIDORIYA, ALONG WITH THE MASTER OF FIRE AND ICE SHOTO TODOROKI!!!" The two respective competitors walked out from opposing ends of the field. Their eyes immediately locked onto one another's once they were within the range of visibility, and if looks could kill, the entire stadium would've perished on the spot.
They slowly walked up to their starting points, and silently waited for the call to begin. The audience seemed to feel the tension as well. Nearly everyone had gone deathly silent, creating an awkward chill for Midnight, who had to break the deafening moment.
"ON THE COUNT OF 3, THE MATCH WILL BEGIN!!!"
Izuku's body became blood red and pitch black.
"1...!"
A large cleaver formed from his left arm, the sound of the liquidy material filling the ears of everyone present. Below his feet, multiple spikes coming out of his feet dug into the ground to create traction for his kick off.
"2...!"
He bent down into a position that allow him the greatest potential boost of speed. The veins circulating his body began glowing a bright orange, and his body radiated a similar hue around him.
Time slowed down while his mind sped up. Every little action and every tiny decision would either be beneficial...
Or fatal.
"3...!"
On that very moment, all of the pent up stress, anger, and tension released themselves.
Todoroki released another gargantuan blast of ice.
Izuku, expecting this, kicked off to the left, faster than any eye could see. The ice itself was faster than anticipated, and as he reached the side of the battlefield, he realized he'd been blocked off.
'Ugh... I've gotta freestyle already?' He quickly lamented to himself, then bent down. He leaped upward, arcing a punch to the ice directly overhead, then broke through entirely. The surrounding ice shattered when the shockwaves rifled through it.
Izuku was airborne, nearly 100 feet above the ground, while everyone watching was looking towards the ice to see if the outcome would be anything like the fight against Sero. This also included his opponent. Given this opportunity, he flung a tendril down towards Todoroki, taking hold of him before he realized anything had happened.
Izuku then used the strength required to lift a truck to pull Todoroki up to his height. The tendril brought his opponent upwards as planned, and he let go of it, allowing the fire and ice user to float freely. He reeled his arm back for another punch, aiming to knock Todoroki out with a midair strike, but before the punch landed, ice surrounded the space between them, while also taking the force of the punch.
Making sure he didn't fall flat onto the unforgiving ground below and die, Todoroki generated a slope of ice below him to allow him to slide downward and fall safely. Izuku, on the other hand, while in mid freefall, trusted his legs to land safely, and decided to attack further.
He grew the cleaver on his left hand to a much larger size, and created one on his right that matched it. Before landing, he swung his arms downward and sent the blades towards the bottom of the ice slope in order to destroy it from the bottom. Once they connected, they completely decimated the base of the structure, forcing Todoroki to create yet another platform to support him.
He landed fairly hard onto the ice, and slid a bit forward due to the remaining forward motion, but managed to steady himself and continue. Izuku also survived the fall, however landed in a far more graceful manner, with his legs taking the brunt force of the intense impact without a single trace of wobbling.
The two shared yet another brief moment of eye contact once they gathered their bearings. Todoroki glared downwards at his classmate from the top of his platform, making his distaste plainly clear. This only fueled Izuku more, though. It brought him the confidence that forcing his way through to Todoroki's mind and breaking the mental barrier that held him back was possible.
"Is that it?! You talked down to us all, believing that you could win this festival with just your ice, but it's futile!!" The recipient of the taunt gritted his teeth, but refused to verbally retort. Following the little comment he made, Izuku dug into ground once more, then leaped through the air towards Todoroki, who responded with, surprise surprise, another sheet of ice.
Izuku expected the ice to remain upright, so instead of punching through, he decided to latch on and dig his way through to prepare for a surprise attack on the opposite end. Unfortunately, he misjudged the glacier, which fell backwards towards the ground with Izuku on the bottom.
The entire crowd, especially those closest to Izuku, gasped heavily when they realized that he was crushed under the massive weight of the ice. The ice itself didn't entirely break on impact, so he was forced to bear all of the weight alone.
Midnight was about to step down from her perch and check on Izuku, but before she reached the ground, she noticed the ice was trembling. Slowly, it rose up from the ground, higher and higher up, eventually reaching the height of an average 15 year-old male.
Below, was Izuku Midoriya, holding a 100 ton block of ice with a single hand.
He pushed the block aside, letting it roll off of the battlefield, created two more blades, and smiled, baring all of his fangs.
"You see, Todoroki? No matter how much ice you decide to send my way, you won't be able to do a thing."
(For reference, this entire fight, from the start of the fight to now, has been about 30 seconds. I estimate about 11 seconds pass before he's crushed, and the remaining time after is how long the rest of what is currently written takes. In other words, this shit happened fast as fuck boi)