For more information on the battles' navigation, please visit here.
As the Representative Battle of the Rainbow starts, Iemitsu blasts open a wall beside Tsuna. Iemitsu states to Tsuna that it was about time he started treating him like an adult.
Tsuna wonders if his dad is even strong enough to combat him. Iemitsu challenges Tsuna to go into Hyper Dying Will Mode, and Tsuna hotly retorts that he could do it on his own, but that he was worried about his dad's well-being. Iemitsu brushes it off lightly, stating that he was worried about Tsuna, instead. Tsuna is angered and enters Hyper Dying Will Mode, with Natsu on his shoulders. Iemitsu challenges Tsuna to come at him with all the resentment he's harbored towards him. Tsuna reluctantly charges at Iemitsu and punches him hard with his X-Gloves, mentally and resignedly commenting that he told Iemitsu so. Iemitsu, however, appears unfazed and comments that the punching brought back memories of Tsuna kicking him as a toddler, then sharply stating to Tsuna that he could put more into the punch. Tsuna activates Natsu's Cambio Forma, punching Iemitsu even harder, but Iemitsu still remains unfazed and tells Tsuna to attack more vigorously. Iemitsu then tells Tsuna to pay attention, as what he was about to do was a real punch. Iemitsu then enters Hyper Dying Will Mode and punches Tsuna, sending him flying far away from the building. As the dust clears where Tsuna lands, Tsuna is incapacitated. Iemitsu radios to the other CEDEF members that Tsuna was down.
Gokudera, Yamamoto, and Ryohei head to the explosion site where Tsuna landed, but are barred by Hibari and Fon, engaging in a battle with him. Iemitsu does not destroy Tsuna's boss watch because he talks with Reborn and allies his team with Reborn's team.