Jim Crocodile Cook

James "Jim" Crocodile Cook is a new student hailing from South Academy who enters Duel Academy in the third year. Well-versed in earth science and Dueling, Jim serves as an ally to Jaden Yuki and the others.

In the manga, Atticus Rhodes revealed Jim's full name as "James Crocodile Cook" (ジェームス・クロコダイル・クック). In this version, James is possessed by Tragoedia and serves an antagonist.

Biography
Jim is an expert geologist and paleontologist, having taken part in an excavation of a Tyrannosaurus in the past and has a crocodile named Shirley, initially believed to be a fake by Vellian Crowler and Jean-Louis Bonaparte, who he carries around in a specially made backpack wherever he goes. Jim regards Shirley as "family" and does not consider her to be a pet. He places great trust into Shirley and often uses her as a judge of good character, which started his friendship with Jaden Yuki. Jim wields a Duel Disk in the shape of a boomerang.

After saving Shirley from an animal trap, Jim injures his right eye. After regaining consciousness, he is imbued with the Eye of Orichalcum by a man who was touched by Jim's devotion to Shirley. The man who gave it to Jim told him it was supposed to have incredible powers when in the presence of a special comet. Afterward Jim kept his right eye bandaged.

During the Duel between Jaden and Axel Brodie, Shirley began acting strangely due to electromagnetic waves coming from within the jungle. Meeting up with Jaden and his friends after Shirley inadvertently attacks Tyranno Hassleberry the next day, he and the group venture deep into the woods to investigate. Seeing another opportunity to claim Duel Energy, Professor Viper reactivates the signals, causing Hassleberry to act wildly and face Jim in a Survival Duel. Hassleberry quickly regains his senses and lashes out at Jim for disturbing his dinosaur monsters but is eventually defeated. After Viper's defeat, Jim is one of the few students that aren't turned into Duel Ghouls when the academy is transported into the desert. Jim accompanies Jaden and co. to an alternate dimension and assists them in defending Duel Academy from the Duel Ghouls. After their journey into a third alternate world, Axel and Jim face Jaden, who has turned evil and begun calling himself "The Supreme King". Jim Duels him in a desperate attempt to bring back his friend from the dark side, using his Orichalcum Eye to see into his heart, where it is revealed that he was depressed over the Duelist's burden that he does not have but needs, according to previous Duelists he has fought, and over the fact that he feels he needs to be evil in order to fight evil. Despite his discovery and attempts to free Jaden, Jim loses and both he and Shirley disappear, leaving the Eye of Orichalcum to fall into Axel's hands.

Although Jim disappeared he used the Eye of Orichalcum to communicate with Axel, helping him to regain courage and to defeat The Supreme King's power over Jaden. He is later discovered to be alive and held prisoner with everyone else who was defeated in a Duel (or "sent to the stars"), in the Duel Spirit World in an alternate dimension by Yubel and subsequently returns to his academy in episode 157.

Manga
Jim appeared in the Yu-Gi-Oh! GX manga, along with the other Overseas Champions, although this time all four of them are from the American Branch of Duel Academy. Here in the manga he is referred with his full first name, "James".

He is possessed by Tragoedia, thus making him an antagonist. James seeks out Atticus Rhodes, catching him in the forest near the Abandoned Dorm and challenges him to a Duel, which Atticus wins, despite Jim's use of the Legendary Planet, The Tyrant Neptune. Jim had been rivals with David Rabb when they were in America, and seeks out Atticus because he defeated Rabb before Jim ever got a chance to. He is then selected to tag with Axel Brodie against Chazz Princeton and Syrus Truesdale, and his team ultimately loses. During the match, he attempts to make it a Shadow Game, but Principle MacKenzie prevents him from doing so.

In the singles matchup, he Duels Bastion Misawa in the forest, and is the only one of the American duelists to make the match into a Shadow Game. He cruelly defeats Bastion with Neptune, laughing afterwards at the closeness of the match. Tragoedia later recalls him to reclaim Neptune, and he is found in the warehouse where Tragoedia has stored his tablet by Aster Phoenix, and later Jaden and the others. He recovers after Tragoedia's defeat, seen before Jaden's duel with Koyo alongside Axel.

Voice/Mannerisms
In the Japanese version, he speaks frequently in English and gives nicknames to his companions such as "Dino Boy" and "Tomorrow Girl" for Hassleberry and Alexis, respectively. In the English dub, Jim has a stereotypical Australian accent, in which Jaden even makes a comment about it, much to his dismay. Jim is also one of the few characters who retains their original name in the dub.

Jim's character is based off of Captain James Cook, the English traveler who was the first European to discover the east coast of Australia and Hawaii, the first to record circumnavigation, and mapped out Newfoundland and New Zealand. Jim's character is also loosely based on the late Australian wildlife expert Steve Irwin, as evidenced from his attitude and sense of humour.

In the manga, Jim is a lot more malicious than his anime counterpart, favouring use of the Shadow Games - ironically, this is similar to David Rabb, who Jim considered a rival. This also isn't a result of his possession by Tragoedia.

Anime
Jim plays a "Fossil" Deck. His strategy relies heavily on the use of "Fossil Fusion" to remove from the game the monsters in both his own and his opponent's Graveyards to Summon creatures of varying strengths dependent on the Levels and Types of the Fusion Material Monsters used for the merger. The monsters created by "Fossil Fusion" follow "reverse evolution" through the Cenozoic, Mesozoic, and Paleozoic eras; the more ancient the monster, the more powerful it is.

He also used an unnamed Fossil Fusion Monster as a means of transportation in the alternate dimension in episode 138.

Manga
In the manga, Jim plays an "Alligator-themed Reptile Deck", which focuses on swarming and Beatdown tactics and later on, Tributing monsters to his trump card, "The Tyrant Neptune".