Gladius is especially known for his short-temper, which causes him to trigger his Devil Fruit powers whenever he gets easily enraged. Like most of Doflamingo's underlings, he treats his "young master" with utmost loyalty as he got angry when he noticed Violet's betrayal, and did not hesitate to shoot Baby 5 while she was assaulting Doflamingo. He values punctuality as well as following and executing orders precisely, and despises those who do not live up to his standards.
Despite, or rather because of, the loyalty he shows for his "young master", he does not seem to be able to distinguish him from Kin'emon in disguise.
Powers and Abilities
As one of the officers of the Donquixote Pirates, Gladius is presumably a powerful fighter. He possesses a great amount of durability, as he was struck by one of Luffy's Gear Second attacks, only to shrug it off and to quickly recover with no visible signs of harm at all and no permanent injuries whatsoever. He also appears to be very fast, easily capturing Kabu and Rambo, and afterwards Thunder Soldier, all known for their high speed.
It seems that when Gladius gets angry, his hair grows to the extent of tearing his hat up. This is a result of his Paramecia-class Devil Fruit ability, the Pamu Pamu no Mi, which allows him to make his own body or any inorganic object he touches to rupture and explode. Gladius also uses this ability for combat. He can use his ability on inorganic objects for a grenade-like effect that upon explosion sends shrapnel injuring his opponents as he did with his helmet. In Dressrosa, although the toys are changed people, they are still considered inorganic, thus enabling him to kill them with his ability. This was shown when he was about to blow up Thunder Soldier.
Weapons Gladius has been seen using a pistol to shoot Baby 5. He is known for his skills in gunnery, as he taught Trafalgar Law how to use firearms.
His arms appear to be equipped with a firing mechanism which he uses in conjunction with his Devil Fruit ability to shoot rupturing bullets.
Gladius was already a member of the Donquixote Pirates, at age 17, when Trafalgar Law joined the crew as a 10-years old; he was instructed by Doflamingo to teach the boy how to use gunnery in combat.
He participated in Doflamingo's takeover of Dressrosa. After Monet opened the gates to the palace, he and the other high-ranking members of the Donquixote Pirates invaded the palace.
Punk Hazard Arc
Gladius first appeared when Vergo called Doflamingo. As Baby 5 attacked Doflamingo, Gladius eventually shot her in order to get her to calm down.
Gladius was talking with Baby 5 about Violet's betrayal and what they should do about it. His top hat began to expand as he became more angry about it, until Baby 5 told him to calm down and not explode. His hair ultimately burst through it and he angrily expressed his disgust of people who do not follow orders.
When the palace was under attack, Gladius intercepted Thunder Soldier, Kabu, and Rampo after they escaped from Lao G. The two dwarves tried to attack him, but the officer caught them and blew them up. He then went after Thunder Soldier, stating he can't outrun him as a toy. He tackled the toy soldier from behind and, while explaining his ability, inflated the soldier's head. Right before it exploded, Luffy knocked Gladius away with a Jet Stamp, saving Thunder Soldier from certain demise. Upon seeing Violet, Gladius ranted about her betrayal and exploded his helmet, hurting her with the helmet's shards.
Luffy, Thunder Soldier, and Violet escaped through a window. After losing sight of them, he ran into Kin'emon, disguised as the young master. Fooled by the disguise, Gladius informed him about Kanjuro's whereabouts.
After realizing that he was tricked, Gladius went to the second floor to search for Luffy and his group.
By the time he found Luffy's group, they already began their assault in the suit room. When Gladius arrived at the room, he was surprised to see Doflamingo's head separated from his body. After Pica entered the room in his stone form, Gladius was once again shocked to see Doflamingo still alive.
It was then revealed that the decapitated Doflamingo was only a copy made of string. After the real Doflamingo appeared and had Pica threw his enemies out of the palace, Gladius stood next to Doflamingo as he initiated his "Birdcage" plan.
After Pica relocated the palace to the Flower Hill, Gladius was seen gathered in a meeting with some of the other officers and lower-rank subordinates at the top of the palace.
He was later seen on the second level of the new King's Plateau guarding the palace alongside Machvise, Baby 5, Lao G, and Dellinger. Once Luffy's allies reached the second level, Gladius told the lower-rank troops to not lose sight of the enemy.
Gladius and his four fellow officers later joined the fray. When Chinjao tried to climb up to the third level, Gladius knocked him down with Landmine Punk.
While Robin, Rebecca, and Bartolomeo were flying over the second level, Gladius attacked them with explosives. While Robin and Bartolomeo were falling, Gladius jumped into the air after them but was caught in Robin's clutches. They later landed on the third level. Gladius and an army of giant toys then faced off against Robin and Bartolomeo.
Gladius launched rupture bullets at his foes, but Bartolomeo blocked it with his barrier. After Bartolomeo used his ability to create a stairway to the fourth level, Gladius launched explosives at Luffy as the latter was making his way up there. Bartolomeo protected Luffy by jumping into the line of fire. After Robin knocked away the toys in the vicinity, she declared that she would not allow Gladius to lay a hand on Luffy.
When the headcrackers became human and were revealed to be Family troops, Gladius was surprised that Sugar had been knocked out again. Gladius then comforted the soldiers by lying to them that they (the Family officers) were going to turn them back into humans once the battle was over, despite knowing that he had completely forgotten about them due to Sugar's power.
Gladius later prepared to fight against Cavendish.
He prepared a destructive explosive attack by swelling and inflating the ground around them. He subsequently initiated the attack with no concern for his troops. However, Cavendish and Bartolomeo were completely protected by Bartolomeo's barrier. Gladius then noticed Robin making her way up to the fourth level. He tried to gun her down, but Bartolomeo used his barrier to block the shots. Cavendish was about to strike Gladius but was interrupted when Bartolomeo came charging with his barrier. Gladius then called for Dellinger to assist him. By the time Dellinger arrived, Gladius was witnessing Hakuba's rampage. Gladius warned Dellinger to stay away, but the latter was soon struck down by Hakuba himself.
After Hakuba was restrained by Robin above, Gladius took advantage of the commotion and started rupturing the plateau with his powers in order to take them both out. Bartolomeo attempted to attack him, but Gladius struck him with poisonous needles from his hair. Gladius proceeded to inflate his whole body, stating if he were to explode, he would shoot thousands of similar needles toward Robin and Cavendish up above unless Bartolomeo could defeat him. Bartolomeo then encased himself and Gladius in his barrier and tried to slit his throat. Gladius exploded, seriously injuring Bartolomeo in the process. Gladius survived, revealing to have been stabbed in the shoulder instead of the neck, and proceeded to erupt the plateau. However, he was shocked to see that they survived thanks to Cavendish using Hakuba's speed to evade the explosion. Just then, Bartolomeo took him by surprise and delivered a powerful barrier-covered punch, defeating Gladius and knocking him unconscious. His unconscious body was later taken by the soldiers of his crew, with Bartolomeo allowing it because he knew Gladius would be unconscious for a few days either way. After Doflamingo's defeat, Gladius and his fellow officers were arrested by the Marines.