A bit of trouble came up when it comes to arranging the teams for Cavalry. With replacing Tokoyami as Goku kinda joined Midoriya without problem, I'd imagine Black Bird Boi could instead join Team Mineta. As for Pony? She could merge into Team Kodai. Though for much of the rest, it'll be more about them trying to defeat Team Midoriya, so canon-wise, there won't be much of a difference.

-The Sports Festival Part Dos: The Cavalry Battle: A Battle of Ice, Fire, and Wits-

The crowd murmurs, some talking of Midoriya, others talking about Goku's flight, and others talking about Todoroki and Bakugou. The rest of the runners crossed the Finish Line, many of them panting hard and some of them dejected, as they knew they lost.

"Congratulations to the Top 42 Runners! To the rest of you, you've done well, but sit back and enjoy, as you get to see the true sifter in play!" Midnight announces. The panel is blank. "The next event is... THIS! The Cavalry Battle!" The crowd applauded, many of them wanting to see this battle. The 42 students murmur slightly on the battle.

"Erm, how are we gonna be split up?" Tsuyu questioned.
"Simple! Up to four students will become a cavalry, and your goal is to snatch up headbands marked with points."
"But how many points are there?" Mina asked, looking pretty impatient.
"I was getting to that, so shut up and listen!" Midnight cracked her whip, the students stopping their murmurs for just this second. "Starting from 42nd place, they will have only five points. 41st, ten. 40th, fifteen, so on and so forth, until 2nd place, who gets a bounty of 205 points. As for First Place... they instead have a ten million point bounty!" Midoriya felt deathly pale at this announcement, as he saw the entire student body, including Goku, looking at him. To the poor boy, it felt like all of them were glaring daggers right into his heart. "You all have fifteen minutes to buddy up and make your Cavalry!" Midnight announced, as kids start to congregate around their groups.

Goku, for all intents and purposes, wants to fight against Momo, who has teamed up with Todoroki, so it turned into a two birds with one stone situation, to his satisfaction.

"Hey, Midoriya!" Goku waved as he approached Midoriya.
"Goku? I thought you were gonna be with a different team! You're in second place, you know!" Midoriya was confused, why is he coming to him as a partner?
"I know, but I kind of want to fight against Todoroki and Momo! They're quite powerful!" Goku quipped right back.
"Count me in too, Midoriya-kun and Goku-kun!" Uraraka said, approaching the two. The duo of them are joyful as they welcomed Uraraka into the party. Their attempt to have Tenya join in had failed.
"I thank you two for your request, but in order to grow as a Hero, I will need to oppose you, Midoriya-kun and Goku-kun!" Tenya said, as he walked towards Todoroki and his team. When it seemed to be like a three-person job, a girl with gadgets approaches Midoriya from the back.
"How about I join your team, Mr. First and Second Place?!" the girl said with incredible enthusiasm.
"Aah! Too close!" Midoriya yelled in surprise, the mysterious girl getting within inches of his face, crawling away from her as he looks up to her. "W-Who are you?!"
"Mei Hatsume, Support Class. I saw your performances, you two are quite the innovative bunch!" she expressed bombastically, eyeing up Goku and Midoriya. "Unfortunately for you, my black spiky-haired friend, I think you're too powerful for my cute babies!"
"Babies...?" Uraraka and Goku said in confused synchronization.
"My inventions, my best creations, my babies!" she says as she sets her babies up, which are Support Items. For Herself and Uraraka, they have jetpack boots. For Midoriya, is a jump pack. "I gotta show those corporate suits sitting way above there my inventions, y'know?!"
"It's for the best anyways. With all the training I've done, I'll be able to fly out of any situation!" Goku said, a bit prideful.
"Alright, Goku, you'll be the Front Horse. Uraraka and Mei, to my sides. I'll be the rider." Midoriya formulated.
"Sounds like a plan, Midoriya!" Goku chimes, reading himself.
"Right, Deku-kun!" Uraraka agreed, getting to Midoriya's right.
"Showtime, ladies and gentlemen!" Mei yelled like a director as she clicks to the left, causing Goku and Midoriya to shudder a bit with how loudly she yelled.

"FIfteen minutes have passed! Now, as this is a cavalry battle, Quirk usage is allowed, but you must not attack with malicious intent, that is attacking without thinking about snatching or defending your headband, or you will get a warning! More than three warnings, you will get the red card and be thrown out of the game!" Midnight announced. "And we shall begin... NOW!" Midnight yells.

Most everyone attempts to attack Team Midoriya, but with the help of Goku's innate strength and speed, alongside Mei's inventions, they are able to bob and weave through the grounded initial game. Any head-on attacks by the teams are met with a feigned explosion from Goku's hands. However, their first obstacle was a surprise attack from Team Mineta! The first few balls pelted their bodies, but before any were able to tag any of their footwear, Midoriya used a 5% arm sweep to start misdirecting the balls elsewhere with a gust of wind, with a few reflecting back and hitting Shoji's boots, immobilizing him, and a shadowed arm that clawed out was met with a blue orb parry, scaring it away. The next obstacle came from Team Bakugou, who launched an attack on Midoriya's team, who were able to dodge it thanks to their technology being unharmed in addition to an explosive parry. A creepy guy from 1-B, Juzo Honenuki, attempts to use his Quirk to trap Team Midoriya, but while Uraraka and Mei sunk in the quagmire, Goku was able to levitate, trying to keep Midoriya up, the group soon was able to escape via Mei's gadgets and Goku's flight, pushing as much energy as he can. Finally, a giant hand came in just as the group lands. Team Kendo were ready to try to snatch the headband with a couple floating hands trying to speed near Midoriya's head, though a precise explosion threw Itsuna Kendo off, with Midoriya able to throw the hands right back at Team Kendo's Setsuna Tokage. However, it was paltry compared to what happens next.
As Bakugou is distracted with Team Monoma stealing his team's headband, Team Todoroki walks around, electrocuting many and freezing others, including Goku and Mei's babies taking the brunt of the electric damage for Team Midoriya, leaving the two teams as the only free ones in the makeshift ice arena, a smorgasbord of headbands on the Ice-Fire student's neck. On their first charge, Todoroki and his team attempted their first snag of the 10M Headband, but it was no use as Goku misdirected them with an explosive feign attack! Any attempt to steal their headband resulted in a counter either by Momo's metal bo or by Kaminari shocking the Saiyan. However, Goku started to feel exhaustion near the one-minute mark, he had never needed to exert himself this much before, especially with the numerous shocks by a now dumbed-down Kaminari. It was then that he heard something, but it was too late for him to do anything.

"RECIPRO BURST!" Tenya screamed, his engines going into overdrive, speeding faster than either the exhausted Goku or the other teammates could react, resulting in the No. 1 headband now belonging to Team Todoroki to all their shock. Team Midoriya was at 0 Points.
"Holy-! That speed, Tenya! How did you do it?!" Todoroki asked in surprise.
"That was my special technique, Todoroki-kun. I can use it for a large burst of speed, but it overloads my engines..." Tenya said, his exhaust pipes expelling a foul black cloud. He then turns around to Midoriya and the now attentative Goku. "I said at the beginning to the both of you and I will reiterate, I'm challenging you!" Tenya shot at them in defiance.
"Hurry, we need to get that headband back!" Midoriya said.
Goku concentrates, relaxing himself, he glanced and saw Todoroki, Tenya, and Momo interacting, figured something fishy was afoot. "We'll need to charge at them with all that we got!"
"There's a final showdown going on near the boundary!" Present Mic spoke, spotting the two near the Out of Bounds Line. "All it takes is for Team Todoroki to keep the ten million headband away from Midoriya's Team and they will have won it!"

With a short yell, Goku flares up his aura, which manifested with a white color instead of yellow, his facials sharpened to determination as he looks at every little detail. The time's now or never.
"Midoriya, I'm ready! Go for Todoroki's headband!" Goku commanded.
"Let's go!" Midoriya said, Mei and Uraraka nodded as they ready themselves! Team Midoriya charged at Team Todoroki, Goku carrying most of their land speed. Kaminari attempts to zap Goku, but his aura dissipates the electrical shock harmlessly with a kiai shout! And as the gap grows ever closer, Midoriya's arm glows with red cracks! Todoroki, fearing for the raw power of Midoriya's arm and Goku's aura, inadvertently started using his fire! Midoriya used a chop to cause a gale wind to disorient the enemy team and dissipate the fires, as Midoriya grabbed at one of Todoroki's headband on his head! However, within the same moment, Goku used his lightning-fast hand to snatch the headband on Todoroki's neck as well! Momo and Tenya's pupils shrunk as they saw that Goku had plucked the right headband and their gambit failed. It was Midoriya's original headband, now back in their possession! He had grabbed the one with the least points, only worth 125 points.

"Goku! I don't know how you realized their trick, but you did it!" Midoriya cheered.
"No way! I thought that was a foolproof plan!" Momo said in distress, Goku chuckles as he pants lightly, shooting a look of challenge right back at them.
"I saw through that slight-of-hand trick, Momo! You won't fool me that easily!" He hands Midoriya the 10M headband.
"Don't blame yourself, Yaoyorozu-kun! Our opponents were as clever as we are! If I had known Goku-kun could move his arms that fast, I would have changed my strategy!" Tenya stated.
"Iida's right, Yaoyorozu. Besides, I bare some of the blame myself. I've severely underestimated Goku's power even without that transformation. Thankfully, even if we can't get it back, we still have enough points to make it to the Finals," Todoroki said, as his team nods, resolved for a final charge on the off chance they can reclaim the headband. Ten seconds! They charge at Team Midoriya again, Goku sets up in a defensive position! Despite the tiny puffs of black smoke, Iida's determination will not allow him to not give up right here! Five seconds! Team Bakugou start coming in, the blonde bomber launching off his teammates, yelling in rage as he attempts to snatch the 10M headband for himself! ZERO!
"GAAAAAAAME OOOVER!" Present Mic announces with a roaring applause following soon after. Bakugou face-planted in the dirt, growling. "Team Midoriya has done it! They've reclaimed their headband from Team Todoroki's jaws! The two, alongside Team Bakugou and Team Shinsou will move on to our third and final event!"

Midoriya gets off Goku, with the latter playfully smacking the back of Midoriya's back, accidentally cratering him.
"Whoops!" Goku gets Midoriya back up and rubs his back. "You alright?"
"Y-yeah, I'm fine, Goku..." Midoriya started to lighty cry. It wasn't sadness or stress, but... "I'm just... so... happy!" he shouts before he flat-out sprouts his waterworks all over the place, drenching Goku and their comrades in tears and planting himself into the ground by the pressure of it.
"You both were amazingly in sync with one another, Deku-kun and Goku-kun!" Uraraka said, happy as she takes off the Boots and Mei takes the pack off Midoriya.
"Mmm... I'll need to make my babies more electric-proof and make them resilient to temperature shock... Thanks for the field tests! I'll happily work with you again when you need it, Midoriya-kun and Goku-kun!" Mei said, waving goodbye. Uraraka looked dejected as she didn't even get mentioned, but she doesn't mind as she's with her friends.
"B-bye, Mei!" Midoriya stopped his crying as she left.
"See ya!" Goku yelled.

"There will now be a Noon break for the Sports Festival, our titanic tykes deserve to have a bountiful lunch, after all! Come back in an hour as you will see... The First-Years TOURNAMENT!" Present Mic declared.

"Midoriya, Goku, I want to speak to you both where there's less prying eyes." Todoroki said, going towards the shade, away from everyone else.
"Hmm, what do you wanna talk about?" Midoriya said, as they go into the shade of the opening arch.
"You two made me broke my pledge. I wanted to win without using my fire side. And yet, I lost to the two of you and lost to my father, Endeavor..." Todoroki said, dejected.
"Huh? Why don't you use your fire side, Todoroki?" Goku asked. "Isn't this thing about showing how we are as Heroes-in-Training?"
"...My fire side is nothing more than a cold reminder of what my father wanted." Todoroki replied, softly. "You've heard about Quirk Marriages, right?" He asked towards Midoriya.
"Yeah, it's been a common occurrence during the third and fourth generations," Midoriya replied. "Back then, some marriages were more about creating the strongest possible Quirk than it was about love-" Then, the red-white haired kid cut him off.
"Right. I was a conception of such a Marriage, to be nothing more than a tool to surpass All Might, since the old man can't do it himself." It went from bad to worse, as neutrality turned to disgust as the story went on. "Day in, day out, my father trained me. All I've ever known was training. No matter what happened, whether it was an illness or my siblings trying to connect with me, my father abused me, calling me weak, isolated me... Until one day, my mother snapped and poured boiling hot water over my left side. She was sent to an institution, later that day..."
"No way!" Goku was startled, Midoriya was severely distressed as they processed the information. A tinge of sadness was visible with the son of Endeavor, before he resumed, looking lightly enraged.
"That was why, until this day, I had never used my fire side. It's nothing more than a reminder of my father, and what he has done to my mother, my siblings, and me. And that's why I will surpass you both, just using my ice! I will surpass All Might himself with my ice!" Todoroki proclaimed, close to a blind rage.
"Todoroki... I don't know what to say...! But I am not All Might. And you are not Endeavor! You are yourself, and your Quirk is yours!" Midoriya said with absolution in his voice.
"Yeah, you're plenty strong by yourself, Todoroki! But you're strong because of you, not because of Endeavor!" Goku chimed in. Todoroki dejectedly smiled a little, as he then looks at the both of them.
"It's all the more reason I will crush you two. Be ready for that point. I don't know if you're the illegitimate love child of All Might or if you're just related to him somehow, Midoriya, but I'll be ready when we fight. As for you, Son Goku, I'll show this entire stadium that your Quirk isn't invincible despite your improvements," Todoroki said, he starts to walk away. Bakugou was hiding from the three of them, hearing in on the entire thing. Holy shit, what the Hell had Endeavor done...? Is that really the No. 2 Hero, or just some kind of monster in the guise of No. 2? Those are questions for later, since Todoroki dragging Goku and Midoriya in only strove to make him angrier, yet more determined to destroy his enemies on the stage.
"Hey!" Todoroki heard Goku's voice as he turns around. "I'll be ready for you in the tournament, and I won't hold anything back!" Goku yelled to Todoroki in challenge.
"Remember that it'll be our battle, and no one else's!" Midoriya added on after Goku said his piece, the three leave before Bakugou slips out. Goku went straight to the cafeteria to get himself a king's feast for lunch, since he feels ravenous!