Tony Tony Chopper/History/During and After the Timeskip

The Straw Hat Reunion
After two years, Chopper returned to Sabaody Archipelago. He was seen following Fake Zoro, Fake Sanji, Fake Robin, and his own counterpart, believing them (excluding Fake Chopper) to be the real ones. After Fake Robin tried to lure Chopper to them with a cucumber, Chopper then witnessed the fake Robin getting kidnapped by some mysterious men. Later when he saw the Impostor Straw Hat Pirates, he was disappointed in his "captain" because they were not going to save "Robin", and he left crying and saying that he would save her himself.



While searching for "Robin", Chopper ran into Usopp and Nami, who were very happy to see him. After he was informed that the Straw Hats he encountered were fakes, he returned to the Thousand Sunny with Usopp and Nami. Franky then amazed Chopper and Usopp with his new upgrades. Chopper got excited wondering what Franky's new weapons are. He was pleasantly surprised when he heard from Rayleigh that Luffy was already in the archipelago.

After arriving at Grove #42, Chopper departed atop one of his enormous bird friends from Torino Kingdom to bring Luffy, Zoro, and Sanji back to the Thousand Sunny. With the assistance of the Straw Hats' new allies, Chopper and the rest of the crew descended into the ocean with their coated ship, finally resuming their adventure after two years.

Undersea Voyage


While sailing under the ocean, Chopper and the crew marveled at the site of the underwater world. He and Usopp also had to keep Luffy and Zoro from doing anything that might endanger the crew. He attended to Sanji after the he received a massive nosebleed. Chopper along with the rest of the crew decided to have lunch, while Franky explained how their ship was in one piece after two years thanks to Kuma. As the ship descends even deeper, the crew marveled at how dark it has become. With their seacow, the Caribou Pirates soon caught up with the Straw Hats and prepared for battle. Caribou jumps onto the Thousand Sunny. Before his crew can follow, his seacow, which turned out to be Mohmoo fled in fear after seeing Nami, Sanji and Luffy, leaving Caribou behind. The Straw Hats then tied up Caribou as he begged for mercy. Caribou claimed that he is an unfortunate victim and not a pirate, Chopper believed him until Usopp pointed out that he is lying.

Chopper then attended to Sanji as he experienced another massive nosebleed, suggesting that they try to rehabilitate Sanji. He listened as Nami, with the help of Brook, Franky and Robin explained about the Sea Currents, but quickly lost interest when Nami starts talking about how salinity affected them.

He reacted with shock when he saw the Kraken. He then screamed in terror when he witnessed the Kraken destroying Caribou's ship. Even though the Monster Trio left the ship using Barefoot Coating to fight the Kraken, the sea monster aimed for the Thousand Sunny. Franky used his rocket launcher to repel one of the tentacles which amazed Chopper, Usopp and Luffy.



Chopper then blocked another tentacle with his new and improved Guard Point. The Monster Trio soon defeated the Kraken, but because they were not wearing life-lines, they got separated from Chopper and the rest of the Straw Hats as the ship went down the underwater current.

When the crew reached "The Underworld of the Sea", Chopper immediately started to look for the missing Monster Trio along with Usopp and Brook. He then noticed the gargantuan size of a school of jellyfish that were floating around the ship. One of the jellyfish put one of its tentacles through the bubble coating. Chopper reached out to touch it but Robin stops him, saying it is probably poisonous, much to Chopper's stunned surprise. When an even larger fish ate the jellyfish he almost touched, it died as a result, confirming to Chopper that Robin's theory about the jellyfish probably being poisonous was correct. The reindeer commented on how scary and dark the Deep Sea is and how the fish in it cannot see too well.

When the crew realized Caribou was gone, Chopper thought one explanation was that he was thrown overboard while going through the downward current. Chopper was scared when Nami suggested that Caribou might still be hiding on the ship. After Franky trapped Caribou in the barrel, Chopper was the first to notice a sudden rise in temperature. He then moaned about how hot it is, saying he could not go on living like this way, and how after waiting two years to see Luffy, Zoro, and Sanji, they disappeared. When the ship is about to be eaten by a gigantic angler fish, Chopper foams at the mouth in shock.

When the under-sea giant, Wadatsumi appeared, Chopper started to cry from sheer terror. He screamed in fear when the Flying Dutchman appeared. He, along with Usopp, was shocked by Brook's frightened reaction to the ghost ship. He was shocked to see Surume suddenly show up and knock out Wadatsumi, and overjoyed with the rest of the crew to that the Monster Trio came back safely. When they were on board, Chopper tackled Luffy, telling him how scared he was.

When the underwater volcano started to erupt, Chopper panicked and was thrown back by the rest of the crew. Chopper exclaimed how hot it was when Nami said the water temperature was rising. When Sanji suffered a nosebleed while talking to Nami, Chopper remarked that it was a bad time to have a guilty conscience. When the crew reached the trench, Chopper noticed how the water was making steam from the heat. When the rocks fell into the trench, he marveled at Usopps new attack. When a stray rock hit Surume, Chopper fell with the rest of the crew to the bottom of the sea.

Upon finally reaching Fishman Island, Sanji suffered another nosebleed thinking about mermaids. Chopper told him that it would be best if he did not see any actual mermaids, as doing so could kill him. He was impressed with Sanji's fiery resolve to die while seeing mermaids. When Hammond approached with his group of sea monsters, Chopper is shocked by their gargantuan size. Hammond gave the crew two options: join the New Fishman Pirates or die. Chopper and the rest of the crew then prepared to enter Fishman Island with a Coup de Burst.

Trouble in the Underwater Paradise
Luffy rejected Hammond's offer of joining the New Fishman Pirates and the fishman prepared to attack. Franky activated Coup de Burst and the ship flew through the bubble surrounding Fishman Island. The ship then fell into a current and the crew got separated. Chopper, Luffy, Sanji, and Usopp were seen again in Keimi's house meeting and getting reacquainted with Keimi. Keimi introduced them to some of her friends, the Medaka Mermaid Quintuplets and took them to Mermaid Cove where they met more mermaids.

As Sanji swam with the mermaids, Luffy, Usopp, and Chopper relaxed. Chopper expressed his surprise that Sanji is back to his normal self, wondering if it was in the chef's nature. He also said that he is glad that Sanji was feeling better, as he had run out of Sanji's blood type in his blood stock. Chopper states that Sanji has a rare blood-type and that he would not be able to treat any more nosebleeds. While Keimi was telling Luffy that Jinbe is not present on Fishman Island, Chopper was seen in the background looking shocked at a sea serpent that has just appeared behind Usopp. When the killifish mermaid quintuplets informed them that a royal gondola is approaching, Chopper, Luffy, and Usopp hid behind cover while Sanji was being covered by a mermaid. The three brothers of the Neptune House appeared, searching for the people who entered Fishman Island illegally. The mermaids denied that they have seen any intruders.

As the three brothers are leaving, Sanji suffered his worst nosebleed to date, forcing the Straw Hats to reveal themselves. As the Ammo Knights started advancing, Chopper pleaded for them to stop and help Sanji, asking if anyone could donate blood. He explained that if they do not get blood for Sanji, he will die in half an hour. Chopper asked if there is anyone who has a blood type of S RH-, going on to say that it is extremely rare. Keimi told Chopper that fishmen and merfolk have the same blood as humans and it is transferable. She was about to explain further, but Hammond interrupted her, continuing her explanation. He explained that there has been a rule in place for a long time stating it is forbidden for humans and fishmen to share blood. He goes on to say how Fisher Tiger supposedly died. After a gruesome battle, Fisher Tiger suffered a critical blood lost and could have been saved with a blood transfusion, but humans refused to help him. Hammond adds that the rule was put in place by humans ages ago so that their bloodline would not mix with "monsters".

Hammond and his group attempted to capture the four Straw Hats, but Luffy repelled them. When a sea monster in the New Fishman Pirates tried to attack Luffy, the Straw Hat captain subdued it with Haki. Chopper and Usopp are shocked by how the monster acknowledged its loss without actually fighting. Keimi stole the royal gondola and helped the four Straw Hats escape. After Usopp noticed Sanji's smirk and Chopper yelled at Sanji to not think about anything as every second matters, Keimi then took the group to the town port.

At the town port, Keimi and the four pirates found shelter in Madam Shyarly's Mermaid Cafe. Madam Shyarly provided them a room where they could treat Sanji. Chopper and the others luckily came across Splash and Splatter, a pair of okamas who happily agreed to donate blood to Sanji. After Sanji received a blood transfusion, Chopper is relieved that Sanji was able to wake up. Chopper also noticed that Luffy got a scar on his arm when he attacked Hammond and his two companions. Chopper checked Luffy's blood and see that Luffy got poisoned by the octopus merman and is amazed that Luffy's body was able to fight against it. Chopper stayed with Sanji to ensure his recovery.



When the Ammo Knights tried to arrest him and Sanji because of Madam Shyarly's premonition and because of the false accusation for mermaid kidnappings, along with the fact that the majority of the other Straw Hats were holding the staff of Ryugu Palace hostage, Chopper used his new Kung Fu point to fight them off, something that the soldiers and citizens thought was a weird animal. Having slightly recovered, Sanji told Chopper that he was going to see the Mermaid Princess, even if it would cost him his live. Chopper scolded him, telling him that if she was beautiful, Sanji might die instantly.

Sanji then defeated the rest of the Ammo Knights and expressed his disappointment of having to give up his chance of going to Ryugu Palace since they were trying to handcuff him. Chopper scolded Sanji for overdoing things, but Sanji snapped back saying what's done is done. Sanji then complimented him on his Kung-Fu Point and the reindeer happily danced while claiming not to be happy about that compliment. When they heard people screaming that a bloodied person is found and needed a doctor, Chopper turned to their direction and said that he is a doctor. Chopper and Sanji then found a wounded Hatchan, who warned them of an impending attack by the New Fishman Pirates.

Chopper then tended to Hatchan's wounds while the doctor and Sanji are met with accusations from the Fishman Island citizens. While hovering above Coral Hill on top of Megalo, Luffy saw them and jumped down to meet them. Megalo, who was holding Princess Shirahoshi in his mouth, reached his limit and spit her out. While the Fishman Island citizens instantly concluded this as a Mermaid Princess kidnapping, Chopper yelled at Sanji to not turn around or else he might die from another nosebleed.

For the sake of his dream, Sanji decided to turn around even if it means death much to Chopper's horror. However, instead of getting a nosebleed, Sanji became petrified. Chopper said that it must have been the effects of the Okama blood transfer. The citizens then tied up Chopper and the group, but were interrupted by the arrival of Vander Decken IX. After Luffy pummeled Decken into the ground, he checked on Sanji. Chopper informed him that Sanji has reverted to his normal state. The princess and the entire group then hopped on Megalo and flew away. After Luffy knocked back Wadatsumi, the entire group headed for the Sea Forest.



After reaching the Sea Forest, Chopper decided it is safe for him to take his time to treat Hatchan's wounds. The group then got acquainted with Franky, Den, and Jinbe. Chopper then told Franky that he was going to lower Hatchan down from Megalo, and he should be ready to grab him. After Hatchan was lowered, Chopper was surprised to see that Sanji is acting like his old usual self in front of Shirahoshi. Nami and Keimi soon arrived and Chopper happily realized that Sanji is finally cured of his nosebleed tendencies. While Chopper made medicine, he listened to Jinbe as he explained the dark past of the fishmen and merfolk as well as the ideals of Queen Otohime and Fisher Tiger.

After Jinbe finished his story, Chopper and Nami had a friendly conversation with Princess Shirahoshi. When Hatchan started explaining Hody's plan, a visual Den Den Mushi appeared and the group watches a visual broadcast by Hody Jones himself.

Hody explained his plan of recreating the Ryugu Kingdom with himself as the ruler and then addressed the Straw Hat Pirates. Once he showed the imprisoned Zoro, Usopp, and Brook, Chopper is shocked. After Hody finished his speech, Luffy resolved to fight him. However, Jinbe told him not to. Chopper and Franky then correctly guessed that it's because they are humans. Chopper then watched Luffy and Jinbe trying to settle their dispute on how to deal with Hody.

Battle for Fishman Island


Chopper later appeared in Gyoncorde Plaza with the rest of the Straw Hats preparing to fight against the New Fishman Pirates. When Franky mentioned a new weapon in the Soldier Dock System, Chopper got on board it along with Usopp, Nami, and Pappug. He kept asking Usopp if he could drive it. He then rode out on the Brachio Tank V, calling himself "Commander Chopper."

When the Brachio Tank IV fell in a pitfall created by Daruma, Chopper was thrown out with the others by Franky. He then went underground, using his new Horn Point and hindered Daruma in making more pitfalls. He launched him back to the surface and when arrived there, Luffy mistook his new form for a stag beetle. Chopper then faced off against Daruma.

Chopper was underground with Daruma when Usopp called out for him. Dosun got behind Usopp and tried to take him by surprise, but Chopper intervened using Horn Canon: Elf to push Dosun back. While Usopp prepared to fight Daruma, Chopper prepared to fight Dosun.



Later, Chopper commented on the new attack from Iron Pirate Franky Shogun, but was shocked to see that Franky was the attacker instead of the robot. Dosun tried to take advantage of this, but Chopper transformed into his new Heavy Point and matched Dosun's T-Shot with a Heavy Gong. As he recoiled from the force of the attack, Zoro commented on the new monster appearance of the transformation, which Chopper willingly accepted.

Later, Chopper was seen rampaging in his 'Monster Point' much to Usopp's surprise. Usopp nervously told Chopper that the situation is not that serious for him to go like that. Then, Chopper turned to him and says that he is alright, meaning that Chopper was in fact still conscious.



After explaining to Usopp that he can use one rumble ball to stay in Monster form for three minutes, he turned back to Dosun and easily knocks out the fishman with his Kokutei Parmei attack. After all the leaders of the New Fishman Pirates had been defeated, the Straw Hats looked into the sky as Luffy tried to destroy Noah. When the Sea Kings appeared and stopped Noah from falling, saving the ship and the island at the same time, everyone on Fishman Island celebrated.

The After Battle Celebration and Departure
Moments later Shirahoshi brought Luffy to the plaza, dismayed to inform everyone that Luffy had lost a lot of blood. Chopper then asked the citizens if any of them has type F blood. He then recalled the law prohibiting fishman-human blood transfusions. Then Jinbe stepped up and volunteers to donate blood, saying that he does not need to follow the law, since he is a pirate. Chopper carries out the procedure.

Luffy invited Jinbe to join the crew, but Jinbe declined, saying that he has some unfinished business. Chopper and the rest of the crew informed Jinbe he is welcome to join whenever he is ready.

Neptune invited the crew to a banquet and the crew partied at Ryugu Palace with the royal family. After partying for a while, Chopper was shown enjoying himself, when Jinbe recounts the conflict between Aokiji and Akainu. Chopper proudly stated he had already heard about it. He then expressed dismay at the statement that the Blackbeard Pirates are hunting strong Devil Fruit users. He believed that he would be a target, but Usopp pointed out that they would not need the Hito Hito no Mi. After the party ended, Chopper was talking with Usopp about the treasure Luffy, Zoro, and Sanji went to collect. He suggested they help them search and was surprised about how high Caribou's bounty is. Chopper and the rest of the crew were later shocked that Luffy challenged Big Mom.

Afterwards, Chopper and the rest of the crew bid the citizens of Fishman Island farewell and promised (except Franky and Zoro) Shirahoshi to take her to the surface someday. The crew began to set sail with the Thousand Sunny and head towards the New World.

On their way to New World, Nami put Chopper to guard while she takes shower using her Shower Tempo. Chopper remarked how the Shower Tempo clouds look sweet and yummy like cotton candy and showed his concern if the crew will be alright with Nami not on the deck. After the crew reaches the New World, Chopper commented on how the sea of New World looks red.

Arrival at Punk Hazard
Soon after entering the New World, the crew spotted an island surrounded by a sea of flames. The Straw Hats then received a distress call from someone who seemed to be in trouble and mentioned something about a samurai. After Luffy decided to go rescue the person, Chopper expressed relief that he was not one of those chosen to accompany Luffy on his exploration mission, stating that he is not good with heat.



While Usopp, Robin, Luffy, and Zoro fought a dragon, Chopper and other Straw Hats that remained on the Thousand Sunny were knocked out by sleeping gas. They, except for Brook, were then abducted by some unknown foes. The captured Straw Hats later woke up in a cell and find parts of a samurai's still-living head. After putting the pieces of the head back together, the group got information from the samurai. Once they decided to break out, Franky used his Radical Beam to blast a hole in the wall, allowing the crew to escape. They ran down through the halls of the complex and stumbled upon a room filled with giant children. The children were excited to see them, but Sanji just wanted to escape the room before they are recaptured.

While their pursuers came after them, the children begged the pirates to help them escape. Nami could not ignore their cries and decided to help them. Sanji, Franky, and Chopper then attacked the men in the gas masks. Nami and Chopper ran away with the children while Sanji and Franky held the enemy back. Since he was entrusted with protecting the children, Chopper was determined to live up to Sanji and Franky's expectations. As they ran, the children tell Nami and Chopper about how they were abducted and that they were inflicted with some kind of disease. Nami was suspicious, and told Chopper to later investigate the children. They then ran into a room with corpses frozen in the walls, floor, and ceiling.



Frightened, the group escapes and met up with Franky, Sanji, and the head of the samurai, and they all ran out of the building and into the shocked view of the Marines of G-5, Smoker, Tashigi, and Law. They immediately turned around and tried to find another exit to avoid any combat. As they were running away, Law used his ability to rearrange the personalities of the Straw Hat Pirates, putting Chopper in Sanji's body and Franky in Chopper's body. After escaping, Chopper (in Sanji's body) helped keep Nami (in Franky's body) from hurting Sanji anymore than she can. The group then reunited with Zoro, Luffy, Robin, Brook, and Usopp at the back side of the Punk Hazard facility. The Straw Hats then tied up Brownbeard and bring each other up to speed on the current situation. After interrogating Brownbeard, they learned about a man known as Caesar Clown.

Kin'emon later left the group to find his torso and Sanji, Brook, and Zoro go out to find him. In the meantime, Chopper began to examine the children and the source of their sicknesses, while Franky (in Chopper's body) experimented Choppers abilities and makes weird faces. Before long, several of the giant children started to feel pain, saying that they need candy usually given to them in order to make the pain go away. However, Chopper stated that the candy contains a drug that the children became addicted to and Luffy's group learns that the children have been experimented on. One of the giant children hit Luffy and the others went on a rampage, forcing Usopp to put them to sleep. Chopper expressed his sympathy towards the children and Luffy's group decided to help the children and found Caesar. The group then tied up the giant children so that they cannot destroy anything else. Luffy, Usopp, Franky, and Robin then left Chopper and Nami to watch the children while they head to Caesar's lab. While they were gone, the Yeti Cool Brothers attacked and gunned down Brownbeard. By the time Luffy's group returned, they had kidnapped Nami.

Luffy and Franky decided to go after the brothers. Franky asked Chopper to give him some Rumble Balls. Chopper gave him one and advised him on how to use it. However, Franky immediately took one, transformed into Monster Point, and went on a rampage while chasing after Luffy.

Alliance with Law and a Plan to Defeat Caesar Clown


After the defeat of the Yeti Cool Brothers, Luffy, Franky, Nami, and Law returned to the hideout. Chopper and the rest were shocked that Luffy formed an alliance with Law. Law then returned Chopper to his body and Franky to his. Chopper then scolded Luffy and Franky for causing damage to his body. When the Straw Hats insisted Law to assist them in helping the children, Law asked to take Chopper with him to help find the medicine that was used on the children. Usopp tied Chopper to Law's hat, while the rest laughed at Law. Chopper is then tied to his nodachi instead.

Law later warped both himself and Chopper to the back side of the facility to began their part of the plan. The two briefly discussed on how they are going to investigate the drugs. They were later seen inside, where Law managed to lead Monet away while Chopper (hiding inside Law's bag) is left in the room unnoticed. Chopper then left his hiding spot and started sneaking around in the facility.

He later found Luffy's group in Caesar's clutches. Before Caesar send them outside to die by the poisonous gas cloud created by Smiley, a piece of paper was hurled at Chopper. Chopper then read a note, which told him not to do anything. He is later seen running pass by Caesar's location, planning to escape the facility. Chopper managed to acquire enough information of the drug and even got a sedative. As he ran through the hallway, Monet notices him.

Chopper later met up with Mocha and explained to her about Caesar's deception and using the kids for his experiments and how if Caesar continued to use them, the children would die before they reach adulthood. Mocha remembered her friends promising to each other that when they get older, they would reunite and go on an adventure. The gravity of the situation became clear to Mocha and Chopper promised that he and the rest of the Straw Hat Pirates would save her. While Mocha guarded the candy in the Biscuits Room, Chopper attempted the hold back the children. He later entered Monster Point and was fending off the children in Building B. However, Chopper was unable to fight without hurting the children and was beaten down. When the Rumble Ball wear off, the children ran past him and made their way to the Biscuits Room. At this point, Brook, Kin'emon, Zoro, Nami, Usopp, and Robin came to his aid. Chopper told them that he was trying to prevent the children from getting their candy with the aid of Mocha. The group quickly ran after the children to the Biscuits Room. Regardless of Robin's attempt to hinder them, they went after Mocha, who was holding a piece of candy. After Chopper told Mocha to run, Monet appeared and told Mocha not to keep the candy all to herself and that she should share the candy with the other children.



Chopper and Nami then tended to Robin, but she assured them that her wound was only a cut. Monet tried to attack them when they attempted to run after the children, but Zoro quickly blocked her. After getting hit by Nami's Heat Egg, Monet dove into the snow and stopped Nami, Chopper, and Robin from leaving by creating a wall to block their path. An enraged Monet suddenly ensnared Nami and Chopper and prepared to bite Chopper. Nami swiftly moved Chopper out of harm's way and Robin used her Hana Hana no Mi abilities to shatter Monet, saving Chopper and Nami from another attack. Zoro then cut down the snow barrier, allowing Robin, Nami, and Chopper to go after the children.

Chopper, Nami, and Robin then tried their best to keep the berserk children from catching up to Mocha. While Nami and Robin hinder them, Chopper sedated them one at a time. Despite their efforts, some of the children managed to get around the Straw Hat Pirates and caught Mocha. Having no choice, Mocha put the entire batch of candy in her mouth as Chopper, Nami, and Robin watched in horror. Despite Chopper's pleas, she swallowed all the candy. Mocha then began coughing up blood, due to the serious overdose of the drug. As the children were shocked at what they saw, Chopper yelled at them, saying that Mocha sacrificed herself to save them. As they rushed to Mocha, Sanji and the G-5 Medical Team finally arrived to help. Some of the Marines have Mocha moved to an examination room so Chopper could. tended to her condition. Chopper then complimented Mocha on her bravery and hoped that he can save her.

Nami, Robin, Sanji, the children, and the G-5 with them went on ahead to Building R as Chopper and the Marines with him treated Mocha. Once Chopper was finished with the treatment, they proceeded to Building R as well. They later ran into Brook and a petrified Kin'emon. Once everyone reached Building R safely, they board a rail car and make their escape.

Aftermath


Sometime after Baby 5 and Buffalo's defeat, Law treated the children's conditions in a nearby tanker. When Chopper thought that Law had done something horrible to the children, he screamed, and repeatedly called Law a murderer. After Law came out of the ship, Chopper demanded to know what he had done to the children, and Law answered by telling him to mind his own business, and that he had just finished cutting them into pieces. Frightened by this blunt answer, Chopper ran inside, and was relieved to see that the children were okay. The kids then told Chopper that Law took out all the "bad stuff" from their bodies and that they felt great, although being cut into pieces was pretty scary. They then talked about Mocha and what she did to save her friends, and asked Chopper if she would wake up. He assured them that she would wake up and that everyone would return home, away from this nightmare. He then left as Tashigi came in and told the children the Marines would take care of them from then on. Later, after Mocha woke up, an overjoyed Chopper hugged her in relief. Everyone then had a feast together.

After the party ended, Chopper and the rest of the Straw Hats began to prepare to set sail again. As they were leaving, Nami told Chopper that Vegapunk would help cure the kids from the effects of the candy. Chopper reacted by saying that it that was very good news. While they made their way, the G-5 Marines put up a banner to prevent the kids from seeing the Straw Hats while yelling things like Marines are justice and pirates are scum. The kids, however, said that they were the ones who saved them, while remembering all the Straw Hats did for them. The G-5 Marines continued to speak ill of pirates and praised the Marines, but Tashigi interrupted them and said that they were a disgrace. The G-5 Marines responded by saying that if they did not badmouth the pirates, they would come to admire and respect them. Eventually the Marines lowered their voices and banners to let the kids say their goodbyes, while Chopper and the rest of the Straw Hats waved them goodbye, as they made their way to their ship.

Chopper and the Straw Hat Pirates were later seen on a Sea Slope, which Law mentions is pretty common in their current area. A little while later, Luffy started to explain that they formed an alliance to take down a Yonko. Chopper continued to treat Caesar's injuries, until he began to say that they are practically making themselves targets to the big shots of the New World. He continued to taunt them, and called them a larger group of idiots and that only death awaited them. Sanji responded by kicking Caesar, which in turn angered Chopper, saying that he was still treating his wounds, and that Sanji could kick him after he was done with that.

Law then proceeded to explain the operations and underworld deals of all the major pirates of the New World and that Doflamingo, also known as Joker, is the one with the most influence in the underworld. Law continued on, saying that Doflamingo's biggest client is Kaido, which greatly shocked Kin'emon and Momonosuke. Law continued to explain the next goal of their plan, which is to cut down Kaido’s forces as much as possible, specifically his army of synthetic devil fruit users. When Law informed the crew that the current number of Synthetic devil fruit users is about 500, Chopper, Usopp, and Nami voted against the plan but without success. Law assured the crew that the number would not grow any time soon, due to the capture of Caesar Clown. Chopper complimented Caesar about his manufacturing of the synthetic devil fruits which made Caesar quite happy and Usopp quite angry. Law then said that it was really Vegapunk that developed a theory on the devil fruits, and that Caesar only applied it, which made Chopper lose all interest in Caesar. Law concluded by saying that the devil fruits are being made on their next destination, Dressrosa, and also warned the crew to not underestimate Doflamingo. Luffy then asked Kin'emon if he had business on Dressrosa and Kin'emon revealed that one of his comrades is being held prisoner there.

Later that evening, Chopper and Usopp went on guard duty while wearing samurai armor. The next morning, everyone read the news about Doflamingo's resignation from the Shichibukai. They saw that the paper also explained Luffy and Law's alliance and the alliance between Kid, Hawkins, and Apoo.

Caesar Retrieval Arc
Breed A group of dark figures board the Thousand Sunny and attack the crew members, ceasing only at the command of a strange man named Breed, who has captured Caesar. Law, Luffy, and Chopper pursue him in the Shark Submerge III, and sneak into Breed's ship. Breed locks Caesar in a cell, and explains his intentions. It is revealed that Breed does not work for Doflamingo, but he is connected to the underworld  He also knows of Caesar's abilities as a scientist, and kidnapped him in order for Caesar to help in creating his dream world. As Luffy's group arrive at the center of Breed's ship, which is designed like an aquarium, they once again get attacked by the mysterious figures. They are revealed to be animals, enslaved by Breed's ability. Luffy defeats their leader, who turns out to be one of the Kung Fu Dugong he befriended in Alabasta. After the Straw Hats left Alabasta, it started a pirate group with other sea creatures to follow Luffy's dreams as well. Breed enslaved the group and is forcing them to do his bidding. Breed arrives, and uses his ability on Chopper, turning him into a pet under Breed's control. Chopper is ordered to destroy Luffy and Law, and, unable to control his body, he uses a Rumble Ball to transform. When Luffy tries to prevent Law from attacking Chopper, Breed manages to attach collars to Luffy and Law as well. Law, Luffy and the other pets are imprisoned next to Caesar.

Breed thinks of Chopper as a cute pet, and decides to dress him up as a girly princess dress. Chopper is wearing a pink hat with a red crown, a dark pink shoulders, a pink dress, four pink bows (first two on his antlers and the other two on his skirt, and wearing a little girl pink bloomers underwear.) Chopper hated this outfit while Luffy laughs.

Later, Tony watches Luffy and Law were forced to fight each other.

The Next Objective
After Law contacted Doflamingo to inform him that they would bring Caesar to Green Bit, Chopper had a meal with the rest of the crew while Kin'emon and Momonosuke told them the story about how they were shipwrecked and drifted to Dressrosa, how Momonosuke was separated from his father, and how Kanjuro was captured. The Thousand Sunny later approached Dressrosa.

After disembarking, the group split into three teams. Chopper was part of the team that guarded the Thousand Sunny. Chopper freaked out when he saw that Sanji was not part of his group.

Momonosuke later played shogun with Chopper, Nami, and Brook. When Brook started singing a song, they heard strange noises and a voice coming from the men's room.

The voice belonged to Jora of the Donquixote Pirates, who invaded the ship along with several of her subordinates. Using her Devil Fruit power, she turned the men's room into abstract art and then did the same to Nami, Chopper, Brook, and Momonosuke. Hoping to lure Jora away from the ship, Chopper and Brook left on the Shark Submerge III while Nami and Momonosuke rode the Shiro Mokuba I, but Jora transformed the ship into art anyway, rendering it unable to sail.

Chopper, Nami, and Brook attempted to fight back and managed to defeat Jora's men and destroy her ship. Jora used her Devil Fruit powers to turn Chopper's hooves and horns into art, rendering them useless. The three Straw Hats then received a call from Law. They begged Law to come save them, but instead, Law ordered them to bring the Thousand Sunny to Green Bit.

Jora later trapped Chopper, Momonosuke, and Nami in a deadly painting that would slowly suffocate them in ten minutes. Brook acted nonchalant, seemingly caring more about the art that was being created than his friends' lives. The skeleton asked Jora to turn his violin and cane back to normal so that he could add accompaniment to their death. Once Jora complied, Brook then slashed her using 'Drawing Song Hitoyogiri', defeating her and causing her power to wear off, turning everyone back to normal.

Later on, Nami's group kept attacking Jora to ensure she was completely incapacitated. They then discussed what to do with Jora and wondered why Law was not handing Caesar back to Doflamingo. Jora proudly informed them that Doflamingo never quit the Shichibukai and explained his gambit to them, leaving them shocked and worried. As they get close to Green Bit, Nami's group was horrified to see Fighting Fish attacking the Sunny. When they saw Doflamingo approaching the ship, they cried in terror but were overjoyed and relieved when Sanji intercepted him.

A Change of Plans
When Sanji was overwhelmed and immobilized by Doflamingo's strings, Nami's group panicked. Doflamingo was about to deal a lethal blow to Sanji, but Law intervened by using Shambles and teleported Sanji, Caesar, and himself to the Thousand Sunny. Law then instructed Nami's group to head for Zou. Nami's group was reluctant to leave behind the other Straw Hats, but they complied when they realized that the ship was facing threats from both Doflamingo and Issho. After blocking an attack from Doflamingo, Law informed the Straw Hats about Doflamingo's Devil Fruit powers and instructed them to go to a place without clouds. Law then took Jora hostage, giving Nami's group enough time to escape using Coup de Burst.

After sailing far away from Dressrosa, Chopper expresses his concern for Law. When Zoro finally made contact with Luffy at the Corrida Colosseum, the group on the Sunny engage in a conference call with both Luffy and Franky's group. After everyone was brought up to speed and learned about the true situation on Dressrosa, Sanji decided to sail back to Dressrosa to carry out their assault on Doflamingo, much to Chopper's dismay.

Through the Den Den Mushi, the group on the Sunny heard the skirmish occurring at the Corrida Colosseum and was shocked to hear that an Admiral was also present in Dressrosa. To make matters worse, the return trip was cut short by the appearance of the Big Mom Pirates, who were after Caesar Clown. Since returning to Dressrosa was not a wise option, Chopper and the others on the Thousand Sunny continue on to Zou.

The Next Island
Chopper and the others managed to deal some damage to the enemy pirate ship when Chopper assumed Monster Point and used Caesar as a net to catch incoming cannonballs that Brook had slashed and frozen with Soul Solid, allowing Sanji to kick them back with Diable Jambe, igniting Caesar's gas and sending the fiery cannonballs crashing into the side of Big Mom's ship. Since none of the crew present knew how to use the Coup de Burst, they eluded the Big Mom Pirates thanks to a fog Nami created. They arrived at Zou the next day. After forcing Caesar to take them on the giant elephant's back, they came across Sheepshead chasing after Tristan. After saving Tristan and running from Sheepshead, they found Zou's ruined city covered in poison gas and the devastated Mink Tribe. Pedro begged Chopper's group to help Inuarashi and Nekomamushi. When Caesar acted pleased on how destructive the poison gas weapon used by the Beasts Pirates was, Chopper angrily beat him up.

Some time later back on the Thousand Sunny, Chopper was eager to go and save Tristan, and had to berate Caesar for wanting to stay on the ship. After the brief conflict with another band of pirates, Chopper yelled at everyone to come to his location quickly.

After fending off Zou's enemies and forcing Caesar to neutralize the poison gas, Chopper and his group then get to work on treating the injured minks, saving them from certain death and gaining their gratitude.

Big Mom's Invitation
Several days later, they discovered that two members of the Big Mom Pirates, Pekoms and Capone Bege, had arrived at Zou. Sanji and Brook then spoke with the Big Mom Pirates members in private. After Bege shot Pekoms in the back for agreeing to let the Straw Hats go, he summoned his men from his body and captured Caesar and Sanji's group, except Momonosuke, who had locked himself inside his room. Bege then took them inside his body to continue the conversation with the Straw Hats. While talking to Sanji, Bege gave him an invitation to the Big Mom Pirates' wedding tea party. Bege also identified him as the third son of the Vinsmoke Family and indicated he would be marrying Purin, the 35th daughter of the Charlotte Family.

As the other Straw Hats reacted to the news, they remembered Sanji's mysterious comment that he was born in the North Blue. After writing a note, Sanji gave it to his friends. He apologized to his crew, explaining it wasn't his intent to hide things from them, but he never expected to face this part of his past again, deciding to put an end to it alone. He then threw Nami, Chopper, and Brook out of Bege's body.

Sanji snatched a rifle from one of the Firetank Pirates and held Caesar at gunpoint to prevent Bege's crew from going after his comrades. As Nami, Chopper, and Brook plead for Sanji to stay with them, Sanji promised that he would return before Bege fled with him and Caesar. His disheartened friends were now left with just a note which made light of the situation.

Reunion with Luffy
After Luffy and his group arrived at Zou, Chopper and Nami resided in Rightflank Forest. Nami was sleeping on a giant sheep mink when Chopper informed her that Luffy and his group arrived. Chopper and Nami then quickly went to greet them.

While feasting with the minks, Chopper and Nami explained to Luffy's group about how the Thousand Sunny group escaped the Big Mom Pirates. When Chopper heard that Duke Inu-Arashi regained consciousness, Chopper and two mink doctors, Miyagi and Tristan, went to check up on him.

After Wanda brought the rest of the Straw Hats to Duke Inuarashi's home, Chopper welcomed them. When Wanda mentioned about a weapon Jack used against the Mink Tribe, Chopper revealed that it was one of Caesar's poison gas weapons.

When Wanda finished with her recollection on the devastation Jack caused and the Mink Tribe's salvation, Chopper decided to visit Nekomamushi and the Guardians. The Straw Hats, Wanda, and Carrot then traveled to the Whale Forest.

After explaining about the circumstances concerning Sanji's departure from Zou, Chopper wondered if they will never get to see Sanji again. Zoro expressed apathy for the situation, much to Chopper's anger. After Luffy declared that he would ask Sanji himself, Chopper told them that Pekoms was left behind, so they could ask him some questions.

After arriving at the Whale Forest, Chopper was told by a reindeer mink, whom he is entranced with, that Nekomamushi was inside his home taking a bath, which shocked him.

When Chopper found Nekomamushi eating lasagna while taking a bath, he yelled at the feline mink that he was not allowed to take baths, as his wounds would reopen, and was supposed to eat light foods and not use his left hand. Nekomamushi replied that he loved freedom as he walked out of the bath, and Chopper yelled at him for ignoring his orders. When he started playing with a ball, his wounds reopened. Nekomamushi ended up in bed, which he claimed was because he wanted to be. Chopper gave him an injection while he played with a foxtail. Nekomamushi claimed that he felt better already, but Chopper smacked him and told him to lie down.

Chopper, Robin, Usopp, and Brook then went to see Luffy, who was visiting Pekoms alongside Nami and Zoro. Chopper was in disbelief to see Nekomamushi following them. After Nekomamushi carelessly injured himself while greeting Luffy and Zoro, Chopper panicked and once again tended to his wounds as Law and his crew arrived. After Law warned them about the threat of Kaido, Nekomamushi partied with both the Straw Hats (except Robin, Franky, and Brook) and the Heart Pirates.

Revelations and a New Alliance
On the next morning, Chopper and his group heard a bell ringing and realized that Kin'emon and Kanjuro had arrived. They quickly rushed to find them, fearing what would happen if the Mink Tribe meets the samurais. The Straw Hats managed to intercept Kin'emon, Kanjuro, and Momonosuke just as they arrived at Kurau City and tried desperately to keep them hidden. However, as Nekomamushi and Inuarashi were fighting, Kin'emon and Kanjuro revealed themselves. Contrary to what the Straw Hats expected, the Mink Tribe welcomed the samurais and revealed that Raizo is safe. The Straw Hats were stunned to learn that the minks knew about Raizo all along and went to great lengths to keep him hidden despite the abuse they suffered.

The Straw Hats were further shocked when Kin'emon revealed that Momonosuke was not his son, but rather the heir to the daimyo of Kuri. Inuarashi and Nekomamushi then took the Straw Hats, Law, and the samurais to Raizo's location in a secret area inside the whale-shaped tree. As they journeyed there, Chopper and the male pirates began fantasizing on what Raizo would be, imagining him to be a stereotypical ninja. When they saw Raizo, they were shocked at his ugly appearance, but still begged him to perform tricks. Raizo initially refused, but relented after the Straw Hats began sulking. They were then awestruck as Raizo performed his ninja arts.

Chopper, Luffy, and Usopp then accompanied Kin'emon, Kanjuro, and Raizo as they stood outside the Whale Tree, expressing their sorrows as they saw the state Zou was in after Jack's attack. When Robin deciphered the red poneglyph hidden in the Whale Tree, Nekomamushi called them back in. Inuarashi then explained to the Straw Hats about the four Road Poneglyphs and they listened in anticipation as he revealed how they can lead to Raftel. When Nekomamushi revealed that Kaido and Big Mom each possessed one Road Poneglyph, Chopper, Usopp, Nami, and Brook were deeply shocked. The Straw Hats were then surprised when Nekomamushi revealed that Momonosuke's ancestors created the poneglyhs. However, the samurais explained that Momonosuke never inherited the knowledge of the poneglyphs due to the execution of Lord Oden at the hands of Kaido and the shogun of Wano. The Straw Hats also learned that Oden was part of Roger's crew and had been on Raftel with him as well as the Beasts Pirates' objective in obtaining the secret that Oden knew.

Right after Luffy agreed to form an alliance with the samurais and the Mink Tribe, the group left the secret room. Afterwards, Chopper and the others learned that Inuarashi and Nekomamushi traveled with Oden and had been on the ships of both Whitebeard and Roger. The alliance decided to split up to accomplish different tasks and meet up again at Wano. Chopper, Nami, and Brook chose to accompany Luffy in his mission to rescue Sanji. However, before they could start their operation, they felt Zou shaking and heard Zunisha crying.

As everything shook around them, they witnessed Luffy and Momonosuke's ability to hear Zunisha's voice. They then heard from Momonosuke that Jack returned to Zou and started attacking Zunisha. On Momonosuke's command, Zunisha sank Jack's fleet with one blow. With the threat of Jack ended, everyone became calm again.

Chopper, Miyagi, and many other minks then treated Zunisha's injured leg. After Luffy retrieved Pekoms and Pedro volunteered to join the Sanji retrieval team, Luffy's group departed from Zou. Everyone, except the Straw Hat members left behind, were shocked when Luffy jumped off Zunisha with his party.