Rubick felt the mood strike him too. He coated his Dragon Horns in Armament Haki and Conqueror's Haki, then launched himself at Chinjao with a Rocket Headbutt.
"Divine Dragon: Dragon Assault!"
Armament Haki met Armament Haki, Conqueror's Haki met Conqueror's Haki, and Rubick's Dragon Horns slammed against Chinjao's iron skull. For a moment, they remained locked together in midair.
Black-and-red lightning writhed around the point of impact. Ripples spread outward, catching some of the spectators nearby and leaving them foaming at the mouth and unconscious.
Chinjao leaned back and drove his head forward again. Rubick answered in kind. They battered their heads against each other a dozen times before their strength finally gave out and both went flying backward.
Rubick got to his feet with a booming laugh. "Now that was fun, old man!"
Chinjao knelt on one knee. He was old, after all, and not everyone could retain their prime fighting strength into old age. On that point, Chinjao had to hand it to Garp.
Panting, Chinjao rose and planted himself in a horse stance. He began growling like a Saiyan, his presence swelling steadily with every breath.
Presence might have been an abstract thing, but the black-and-red lightning bursting from his forehead under the force of his Conqueror's Haki was plain to see.
Rubick knew Chinjao was preparing his ultimate move. He transformed into a six-meter-tall Half-Dragon, evening out their difference in height.
A dozen seconds later, Chinjao's power reached its peak. He roared, "Hasshoken Secret Art: Cone-less Dragon: Cone-less Nail!"
Paired with his old, cone-shaped head, this secret art had once been devastating. But Chinjao's forehead was flat now, and he could barely bring out half its power.
Rubick wasn't worried in the slightest. Even Luffy had knocked Chinjao down with one punch in the manga. Was