The snow on the fields in Hokkaido had melted, revealing the ground without any disguise of green. All over the place were drought patches in a place supposedly be under climate control for mass agricultural production. An aerial exchange of blows and slashes etched its mark more and more into the surrounding nature as the heat dissipated in the form of gaseous ground.
Tomiya swirled around mid air, delivering a series of capoeira take down trying to bind the opponent's limbs. The speed of the latter outpacing him but not to the extent of allowing for a simple counterattack. Because both sides had high firepower and comparable resistance to heat, the decisive aspect was entirely technical: who could sustain themselves longer would win.
For the opponent, clad in modern armor covering all body, she was controlling the propulsion from the various "exhausts" on her backs and below her feet to weave around the web of flames Tomiya was making. The lines making up the constructed expanded and contracted in reverse but they missed their target. Both sides blurred in and out of sight, only visible when clashing or delivering a hit capable of bypassing the other's defense.
The two reached the cityscape.
Using the heat from his feet to create footing in the wall of the large building he had managed to put in between the two, Tomiya tried to reign his quirk back into control as he felt its strength increasing for no reason. His fine control had been reduced, harming his precision but for his opponent, more firepower was all she cared about.
'That bitch ... she is getting the better of me!'
He kicked off the wall and began free falling, escaping from bisection as the upper section of the building slid following him. As more and more heat signature flared up following the initial large one, he ducked and weaved between small buildings. Using a river-crossing tunnel, he laid spikes constructs inside to chip his opponent. Using his flames as a decoys, he deployed them before him with body temperature fool out some of the slashes.
With his face half an inch off the ground, he sped up, exiting the tunnel with tens of him drawing the aggro away.
"So slippery. Has Hokkaido brought you some sense in dodging? That's so unlike someone having daddy issues," Said the attacker as her fire claw met vacant air.
"And for someone so stuck up trying to beat her own dad, you are much more reasonable now. As a villain that is," commented Tomiya as his shield of fire blocked the hot edges trying to dice him.
"Why are you even here, Shori?" , commented Tomiya as both sides engage in hand-to-hand combat.
"And aren't you having such a fun time playing house with that master of yours?", spoke Shori as one flaming exhaust died down behind her, the thermal energy forming into an edge trying for a clean decapitation.
The target used her body as a wall to redirect the explosion force, dodging with a hair-width distance. Tomiya formed his flames into a cuff binding both of them. three-punch combo landed on Shori's face. She fired back by redirecting the fourth punch and twisted Tomiya's arm but the man used it as a whip to slap her face and got the arm back into place. The superheated palm struck and melted some of the mask, forcing Shori to remove it to prevent suffocation.
'Almost there. The greenhouse.'
Bam! Bam!
A massive green house spanning acres, responsible for the upkeeping of exotic tropical plants for domestic consumption, now had 2 hole on its side. The delicate plants inside quickly died off as the heat of the exchange scorched any water. ago. Now the two were in the flower section of that greenhouse.
"This feeling in the plants!"
The previous handcuff was destroyed and Shori was keeping a distance away from Tomiya. She now needed to get serious. The armor plating fell off one by one, showcasing Shori in a leotard to allow airflow and better temperature control. For Tomiya, his clothing had mostly been burnt off, now the only thing he was keeping on was his bottom outfit as his chest laid bare to the environment.
Both of them knew what needed to be done to finish this fight: Their ultimate. Unlike their brother who quirk was a heterogenous mix of both of the parents, theirs were more homogeneous, allowing them to mix and match the ratio and usage of both sides to their benefits.
From Shori's chest outgrew patches of white frost as her body began to cool down to almost hypothermia as the flames surrounding her became the same color, hot enough to evaporate the metal constituting the floor she was standing on. The layer of ice continued to expand, filling the vacant spots to form an armor with ventilation and circulation network for heat exchange. Shori was surprised seeing how less draining the process had been, an evidence for the weird power-up her brother in front of her must have also noticed.
Tomiya's approach was to make his solid flames even more concrete, to materialize the heat and plasma into building blocks he could use to fill the world with. The original purpose for this advanced style of quirk manipulation was for protection and counter-attack with a dash of higher-tier manipulation of quirk. Even he had to take a moment to adjust to the enhanced output.
An explosion blew the greenhouse apart. A wall of flame ate its way through the pillars holding up the glass roof and even the debris falling off. Both sides unleashed their most lethal attacks. Shori used the air surrounding Tomiya to form a plasma cage, her expression crunched together as her control raised the temperature and pressure while stripping him off breathable air. Tomiya dug his way under using explosion but his opponent sensed the movement.
Focusing the large volume of plasma into a single point, she directed it to her feet and thought:
'Supernova'