When does Ace appear in One Piece?

Luffy and his Straw Hats crew sailed towards Arabasta with Chopper, who was now one of the members of the Straw Hats. Chopper was lost in his thoughts and memories of Drum Island when Usoop noticed him. He asked Sanji and Nami whether Chopper was alright. Sanji said that his first trip as a "man" was a rite of passage. As Chopper said, he is leaving for his new adventure.

Luffy keeps the others entertained with his "nose chopsticks" trick. Soon after, the boys attempt to include Chopper in the fun, with Usopp offering him a drink, Sanji asking him to sing with them, and Luffy offering him nose chopsticks. He slips away, still a little uncomfortable with the attention. Nami noticed Chopper and told him that his new friends could occasionally get a little out of hand. Chopper gradually felt relaxed and happy to have friends.

Vivi was warming Karoo with a blanket, who she had discovered frozen in a river. Zoro makes a joke about his fall. Chopper questions Karoo about it and discovers that he had dived in after Zoro, believing he was in danger. Nami punches Zoro after hearing this.

Chopper explains that he can now communicate with animals. Nami is surprised by this ability, which he has in addition to his medical skills. The others ask what she means by medical skills, and they discover that he was trained to be a doctor by Dr. Kureha. Luffy was under the impression that they would acquire a cool talking reindeer with seven transformations. Sanji had assumed that Chopper was their emergency food.

Chopper remembers his medicine bag, which he believes he left on Drum Island. Nami then shows him his medical bag and tells him that it is inside the sleigh. Chopper has no memory of packing anything and thinks Dr. Kureha must have left it there for him. Later, Chopper tries the nose chopstick trick, and the fun goes on as Usopp raises a toast for the new crew member. Chopper then said he had never had this much fun in his life until now.

Kureha and Dalton continue to converse on Drum Island. Dalton begins discussing his plans now that Wapol has left. He had intended to leave to atone for his past work along with Wapol, but he has since realized that he may better atone by assisting in the kingdom's restoration. Kureha believes he is qualified to rule the new country.

The Isshi-20, who Wapol had earlier commissioned, vow their devotion to Dalton, pleading with him to let them aid the country. Someone rushes up to Dalton and delivers to him the wanted poster for Luffy. He claims that a young man entered Robelle around a week ago. He noticed that it didn't snow that day, which was unusual. The young man was Ace. He was tall and wore a black outfit with a straw hat.

He then handed the man a wanted poster and said he was searching for a man wearing a straw hat. He was told that if Luffy returned, he should inform him to hunt for Ace in Arabasta within the next ten days. Kureha mentions that the Will of D. is still alive after recognizing the name on the wanted poster, revealing that the previous Pirate King's name was Gol D. Roger.

The following day, Chopper observes the ocean's size from the Going Merry's bow alongside Luffy. A huge bird flies past and Luffy yells out to it. The bird begins to fly toward the boat and glides just above the bow, catching Luffy. Chopper panics, believing Luffy has been taken. Zoro instructs Chopper to relax and not worry about Luffy unless he calls for help. Luffy grabs the giant bird's beak, uses Gomu Gomu no Propeller to bring it down, and then gives it to Sanji to cook. Nami informed the crew that they would be arriving at Arabasta very soon.

Chopper wondered why they were going to Arabasta, and the crew members told him that they were going there so that Vivi could return to her home, Arabasta, as they wanted to stop Crocodile (one of the Seven Warlords of the Sea) who was trying to destroy the governing body of Arabasta.

Crocodile uses his status as a World Government privateer to undermine the kingdom through his crime organization, the Baroque Works. Vivi explains the group's structure, with the five Officer Agents pairs reporting to Crocodile, the eight Frontier Agents groups reporting to them, and their subordinates totaling roughly 2,000 men. The crew determined that if Crocodile's goal was to take control of Arabasta, he must be bringing the whole force of Baroque Works to the area to help him. Luffy seemed to be only interested in beating up Crocodile.

Mr. 2 Bon Kurei has arrived and is punishing his navigator. They had been assigned to killing Mr. 3 but had somehow missed him. They return to Arabasta to continue their task. Meanwhile, back at Baroque Works' headquarters, Crocodile and his Baroque Works employee, Miss All Sunday, discuss the increasing possibility of pirate attacks on Arabasta.

• Chopper joins the Straw Hats.

• Chopper is now able to speak to animals.

Q. In which episode did Ace appear for the first time?

A. Ace first appeared in the Drum Island Arc in Episode 91 titled “Farewell, Drum Island! I'm Going Out to Sea!."

Q. Is Ace Luffy's elder brother?

A. Yes, Ace is Luffy’s elder brother.