Zoro’s past was expanded upon in the anime. Zoro was a traveler who went around defeating dojos for their signs. However, there was one person Zoro could not beat – the sensei’s daughter, Kuina. In the anime she is the reason he joins her father’s dojo in the first place. Kuina’s father made a deal that if he could defeat her Zoro would take the sign. If not, Zoro would have to train under him. When given the opportunity to use as many swords as he wanted, he grabbed as many as he could carry and faced off against Kuina. He lost and was told he had to start with one sword before he could use more. As per the consequences of his loss, he trained at the dojo as promised.
In the manga, Zoro enters to see her dead body, eyes covered and surrounded by the students and accuses her of running away, in the anime no such scene is shown, but a funeral takes place for her instead, though later on “Ocean Dream” arc in the anime, the original manga scene is shown in a flashback.
His story is extended also in the anime by showing the time he first met and befriended Johnny and Yosaku. They cash in when Zoro takes out a large bounty and, given they pay his tab at the bar he was at for his food, can keep the rest of the money for themselves as an apology for taking their ‘head’. Later,Dick appears in the town with his horde of bandits, who proceed to loot the town. Johnny and Yosaku watch as a child tries to stop the thief to no avail. Johnny convinces Yosaku that they must stop him, to which Yosaku reluctantly agrees. The two are no match for Dick, but luckily Zoro comes to claim the bounty on Dick’s head to pay for a Katana that he broke. After a complete victory by Zoro, Johnny and Yosaku look up to Zoro and start to call him “Aniki”.
Straw Hat Separation
His adventure in Shikkearu Kingdom is also extended in the anime.
Not only did Perona refuse to give Zoro his swords back, but she also tried to turn Zoro into her servant by using her Devil Fruit powers. She got as far as managing to dress Zoro like her former subordinate, Kumashi, while he had passed out before he woke up and left the room in search of his swords. In the anime, Zoro’s training will begin by defeating the leader of the humandrills who copied the swordsmanship of Mihawk.
In most fillers, his lack of direction is further ridiculed as he has gone in the wrong direction even though his guide was still pointing in the correct way, and even turning to the right on a straight path.
Also, ever since episode 111, Zoro has been called marimo (moss-head in the dub) by Sanji in reference to his oddly colored green hair.