Luffy was only seven right now. He had no concept of Haki at all. He would not begin to grasp it until after the Summit War in the future.
But that did not trouble Amon. Even without saying "Haki," he could swap in another explanation.
"This card is very simple. It lets you toughen up your body for a short time and unleash incredible strength."
"With this card, Luffy, you can beat Ace easily. Forget Ace, you could even take down the Lord of the Coast without breaking a sweat."
"Sugoi! So amazing!"
The moment Luffy heard that the card was that powerful, that it could even beat the Lord of the Coast, stars lit up in his eyes again.
Aside from food, what Luffy craved most was strength.
If he wanted to become the future Pirate King, how could he do it without power?
"Big brother, big brother, let me try it!"
Now that he knew how powerful the card was, Luffy could not wait another second to experience it.
"Alright. Luffy, hold this card and repeat the word 'use' in your heart. That is all you need to do."
Amon smiled faintly as he handed the card over to Luffy.
"Use!"
The moment his fingers closed around the Armament Haki trial card, Luffy activated it without hesitation.
As the word left his lips, the dark card in his hand vanished into thin air. At the same time, Luffy felt a warm current surge through his limbs and bones. In an instant, his whole body felt overflowing with strength.
He had the sudden feeling that with one punch, he could knock out a bull… no, a bear.
"Gum-Gum Pistol!"
With so much energy coursing through him, Luffy could not sit still for even a moment. He immediately used his newly invented move, the Gum-Gum Pistol, hammering the sea surface all around.
As his small fists, now wrapped in black Armament, pounded down, the calm water exploded as if hit by bombs. Waves blasted outward, and several fish were flung straight up onto the shore.
"Sugoi, that is awesome!"
Looking at the destruction he caused, Luffy's eyes shone brighter than ever.
"Roooaaar!"
The distant sea suddenly churned violently. A massive Sea King burst from the water, brown-gray hide slick with foam, red eyes glaring, blue-striped fins cutting the spray.
It was the same Lord of the Coast that had bitten off Shanks's left arm.
The moment it appeared, the townsfolk working on the dock were terrified. Their hands and feet shook, and after a brief stunned silence, someone let out a scream. Everyone dropped their cargo and bolted for safety.
To ordinary people, the Lord of the Coast was a monster that could take their lives in a heartbeat.
"Gum-Gum Pistol!"
While everyone else was fleeing for their lives, Luffy did not run. His eyes were full of fighting spirit. The rush of strength inside his body made him desperate for a target to let loose on.
Besides, this Lord of the Coast had once eaten the arm of the man he admired most, Shanks. Today, he was going to avenge Shanks.
The Lord of the Coast had been napping peacefully in the water. Rudely awakened, it burst out from the sea and immediately recognized Luffy.
Enemy meets enemy, and hatred flares on sight.
They charged at each other in an instant.
Bang!
When they collided, the surface of the sea exploded again.
The loud noise startled everyone drinking inside the tavern. They spilled out into the street in a rush. Even the bar's proprietress, Makino, hurried outside.
When she saw that the one clashing with the Lord of the Coast was Luffy, her soul nearly left her body.
She knew exactly who Luffy was, and she adored the little boy.
"Village chief, village chief!"
One glance was all it took for Makino to panic. She raced off toward the village chief's house for help.
While Makino was running for assistance, the battle between Luffy and the Lord of the Coast reached its climax.
With Armament strengthening him, Luffy was on a completely different level. A minor Sea King like the Lord of the Coast stood no chance against him.
Within a few punches, Luffy had beaten the giant beast down in the water. The Lord of the Coast's massive head was covered in bulging lumps from Luffy's fists.
"Yeah! I won! This is amazing!"
At first, Luffy had not been too confident. But he had not expected to knock the Lord of the Coast unconscious in just a few blows. He immediately threw his hands up and cheered at the top of his lungs.
On shore, the townsfolk stared in shock, eyes bulging. Luffy had actually defeated the Lord of the Coast.
Amon, watching from nearby, was equally stunned.
He had known that Armament Haki was strong, but when he saw the sheer size of the Lord of the Coast, he could not help worrying for Luffy.
Of course, at the moment he was just an ordinary person. Worrying would not help him do anything, so he simply hid inside the ship instead.
His ship might look shabby on the outside, but its defenses were incredible. According to the system, even the ancient weapon Pluton's warship could not blow it apart.
Amon only half believed that claim, and it was not something he could test anyway.
But the merchant ship's durability was undeniable. The battle outside had been intense, yet inside the ship, Amon did not feel a thing. That alone proved how sturdy it was.
"How about it? Big brother did not lie to you, did he?"
Once the battle ended, Amon stepped back out onto the deck.
"Mm, mm! Big brother, you are really amazing. I feel like my whole body is overflowing with strength right now!"
Luffy's admiration for Amon now was no less than his admiration for Shanks. His head bobbed up and down like a pecking chick as he nodded furiously.
"That card has a time limit. It will disappear in about an hour. If you want to beat Ace, you had better head out right away."
Amon still wanted Luffy to go over and help him with advertising. He knew Ace and Sabo had stashed a good amount of treasure over at the Gray Terminal.
"Okay! Ace, here I come!"
Luffy shouted, eyes burning with fighting spirit, and dashed toward the back mountain.