Gray's power is simple. He can enhance the functions of any part of his body. For example, he can increase the power of his punches by amplifying his arm. Of course, arm strength is not the only factor in punch strength; the core of the body needs to be strong too.
However, after eating the Amplify Power Fruit, his body was enhanced. It is the immediate effect the fruit gave to its users. His body without any enhancements from his power is now stronger than a regular human by a large margin.
Because of that, he got a naturally strong core. And amplifying it would result in a much stronger core.
Users of this fruit need to have a very thorough understanding of the human body. Gray's grandpa even once said that with enough mastery and deep understanding of one's own body, they can't literally die, as they can enhance their healing factor.
However, Gray's understanding was not that deep, and he can only use his power in a straightforward way.
There are limitations on his enhancements, of course. For example, he can only enhance overly complicated functions twofold. The brain is a complicated thing and has many functions; hence, he could only enhance it twofold.
Body parts like arms, however, have simple functions and are not too overly complicated. He could amplify his arms tenfold.
His amplification is capped at twentyfold, so he could not amplify all body parts simultaneously. He needs to strategize what part to enhance.
With his arms and legs amplified fivefold and his brain, core, and heart amplified by twofold, he's on sixteenfold amplification right now. This proves how strong Ace is.
Here I come!
This time, Gray initiated the attack. He rushed and threw a punch straight to Ace's face.
But Ace did not allow himself to get hit. He bent forward and slightly moved his head sideways and threw a punch aimed at Gray's torso.
Gray, with his reaction time enhanced, saw through the attack and twisted his body to avoid the attack. While doing so, he kicked Ace in the back.
Ace did not react in time and could only make himself a few thousand tons heavier. He was only thrown for a few meters since he was able to make himself heavier, slowing down his momentum.
Gray did not immediately follow up an attack, as his leg was slightly numb from the impact.
It felt like hitting a giant boulder!
Ace grunted and steadied himself. He turned around and faced Gray, his face grim.
He seems like a different person now. He can react to my attacks, and he is much faster. I need to become much faster, and to do that, I must use 'that' technique.
Ace closed his eyes and took a deep breath.
Feather Body.
With a single kick on the ground, Ace disappeared.
Gray was surprised and was about to look around when suddenly a fist came from his right, aiming at his face. He was able to react in time and moved his head backwards.
He was about to give a punch of his own, but Ace disappeared again. A split second later, another fist came rushing straight through the back of Gray's head. Thanks to his incredible senses, Gray was able to react in time and ducked. He quickly turned around, but Ace disappeared again.
Skin Amplification, Fourfold.
Gray's ability to feel his surroundings was significantly enhanced. He can faintly feel the vibrations of the air around him, allowing him to dodge Ace's incoming attack as if he anticipated it.
This time, he was finally able to see Ace. Ace did not disappear. He just moved so fast that it almost looked like he teleported.
Gray opened his eyes and chuckled.
"You're really fast, Ace. The fastest I've seen until now."
"To be able to react and dodge my attacks in this state, you're indeed something, Gray."
Ace's voice came from behind. Gray turned around, and there he saw Ace.
Ace Face looked strained. It's evident that the technique he used just now is very draining to his stamina.
By making his body as light as a feather, Ace was able to move very fast. However, running would slow him down in this state, so by kicking the ground very hard, he can move in a straight line very fast. However, to change directions, he needs to kick the ground again, making delays in his movements and allowing for opponents with strong senses to see him. And he could only move for five meters before slowing down.
Hence, in order to become undetectable, he needs to constantly kick the ground. Someone with great senses would be able to see Ace's figure for a split second every five meters before it disappeared again.
One drawback is that he cannot increase his weight during this state, as the weight would slow him down, so his attacks won't be enhanced.
More importantly, he could only maintain this state for a minute of nonstop fighting. After a minute, he would slow down.
Ace kicked the ground and disappeared again. This time, Gray was ready. When a fist came from the right, he moved his head backwards. However, he did not even finish moving when another fist greeted the back of his head.
He managed to dodge narrowly by moving his head sideways.
Gray was using his maximum focus at this point, yet he could only dodge. Before he could even find the chance to counterattack, another fist would come straight to his face or body.
However, a lapse in Gray's focus costs him a punch in the stomach. Gray's focus broke, and he could not dodge Ace's combinations anymore.
Punch after punch. To the face or to the body. Gray felt it all.
What's worse is that because of his amplified skin, he felt the pain a few times greater. Luckily, with his enhanced skin and muscles, the pain would quickly disappear.
After a few seconds of nonstop barrage, Gray's whole body was full of bruises. His shirt had been torn. His mouth was dripping with blood.
Not even his amplified skin and muscles could protect him from Ace's attacks.
Unstoppable. He's unstoppable...
This is the only thought Gray could think of.
He tried focusing on Ace again many times, but the pain would not allow him.
Many seconds later, Gray started to notice something. Ace's attacks have become slower. Without minding the pain, Gray could sense that Ace's attacks were slower than before.
Knowing this, Gray ignored the pain and focused on his surroundings. A split second later, he threw a punch at his right, seemingly hitting nothing.
However, his fist made contact with Ace's shirt. Seeing this, Gray grew determined.
Ace was surprised too. But he gritted his teeth and ignored the pain in his legs.
I can't drag this on any longer!
Ace appeared behind Gray, but it was as if Gray saw through Ace's movements; he turned around and threw a punch right at Ace's face.
Ace threw a punch at Gray's fist too, ignoring the punch coming straight to his face.
"Arghh!"
Both of them shouted.
"Twenty-ton Punch!"
"Arm amplification, tenfold!"
All of Gray's enhancements deactivated, and Ace's speed went visibly slower.
At the same time, both their fists hit each other's faces, causing a loud bang and both of them to be thrown to both sides of the training grounds.
None of them stood up. They just lay on the ground, still reeling from the pain.
I... won...
The both of them had the same thought before fainting.