The whole place was surrounded by flames, lava and dragons. The temperature was so high that they all had to protect themselves with Usuki energy.
This is because proper distribution of Usuki energy could nullify burning as well as freezing but the protection period varies depending on the training, experience and endurance of the Usuki warrior. this is the reason why they survived the freezing effects of the sun king's attacks.
Anyway, they charged at the Fire lord who had now become very fast due to the high concentration of heat and flames which overwhelmed Hatashi and Tiatsuri but they didn't let up for even a second.
Finally, in a blink of an eye Kaitara joined the fight. She and Tiatsuri who had already activated three of their Takudas early in the fight, put the pressure on the Fire lord while Hatashi stayed back and then performed the water technique: water vortex which was a large amount of water shaped like drill. This attack evaporated all the water in its path before it set course for the Fire lord. When Tiatsuri and Kaitara saw this, they jumped back in order to escape the wave, but the Fire lord wasn't done yet. He tried to evaporate it with his flames.
Nevertheless, Hatashi had already prepared for this. Tiatsuri immediately came from behind the Fire lord.
"Storm technique" Tiatsuri said from above.
"What the…" the Fire lord could not complete his sentence as he was amazed by Tiatsuri's speed.
"Jolt!!!!" Tiatsuri exclaimed and then a strong bolt of lightning came from above and struck the fire lord which created a giant shock wave as it resonated through Hatashi water vortex attack. Due to the sheer scale of the attack, Hatashi, Kaitara and even sensei Hashiro had to jump on a tree to prevent the lightening from shocking them to death.
When all the water dried up the saw smoke and then a recognizable silhouette surfaced. It was Tiatsuri. He survived the attack but with severe injuries. Nevertheless, Kaitara healed and he became better. Unfortunately for them, the Fire lord was burnt to ash. Although this was an assumption because his body wasn't found.
Anyway, at the end of the day, they rested at the forest caught dinner which was a wild boar, and they ate till their hearts content. They set up their tents and slept peacefully after talking about their fights and journey's.
The next morning, they began went on a journey to Karuta village to ask about the location of the sun king the leader of the seven evil Feudal lords.