Magellan has been a prison guard at Impel Down for many years prior to his debut in the Impel Down Arc. After the events at Saboady Arcipelago, Luffy learned that his brother has been sent to Impel Down and is awaiting execution at Marineford. While Luffy was going through each level to get to the level where Ace was at, Magellan learned of Straw Hat's infiltration. In level four, Magellan confronted Luffy and Bentham. He promptly defeated Luffy who was already exhausted from going through all the levels and gravely poisoned him in the process.
Magellan had Luffy sent to Level five for his imprisonment. After the incident, Magellan tries to gat things back in order. Unknown to Magellan, Luffy had recovered from his fatal poisoning thanks to Emporio Ivanko. Magellan had his men escort Ace out of the facility but the Blackbeard Pirates had arrived at Impel Down with the intent on recruiting new members. He confronted the Blackbeard Pirates and poisoned them. Magellan tried to also halt all prisoners from exiting Impel Down. He later learned that Bentham has assisted in the prisoners escape by playing the role as an impersonator of Magellan. Infuriated by Bentham's action, Magellan was about to fight him.
After the events of Marineford, Magellan took responsibility for all the mishaps that occurred with the prisoners escaping from the compound. After the time skip, it was revealed that Magellan had been demoted an Hannyabal has usurped his position as head jailer.
Magellan ate the Paramecia-type Venom-Venom Fruit which allows him to be secret poison from his own body. With this, he uses this poison to create a huge monster known as the Hydra. Also, anyone who is coated in his poison will only have 24 hours to live as seen with Luffy (though he surivies later on).
- Magellan is one of few characters in the series not to be fully defeated by Luffy at all in battle. During the first fight, Magellan defeated Luffy. During the second fight, Magellan shifted to his most deadly poison that forced Luffy to retreat.
- Magellan is the first character to have a devilish appearance with the second being Caesar Clown.