The eldest son of the Scamander family and Newt Scamander's older brother by eight years. As of 1927, he is 37 or 38 years old. He holds a high-ranking position in the British Ministry of Magic as the Head of the Auror Office, a major department within the Department of Magical Law Enforcement. Born: Around 1888 Family: Younger brother: Newt Scamander Occupation: Auror for the British Ministry of Magic (Head of the Auror Office) Education: Hogwarts School of Witchcraft and Wizardry, 🟡 Hufflepuff House Like his brother Newt, he attended Hogwarts. Incidentally, Newt was expelled after taking the blame for a dangerous magical experiment caused by his best friend, Leta Lestrange. In the first film, Theseus appeared only by name, but even then, he was known internationally as a powerful wizard and a "hero of the First World War." Beyond the high level of magical skill expected of the Head of the Auror Office, he is a model figure who rose to his current position through his strong social skills and by consistently meeting the expectations placed on him as the eldest son. While he is obedient to "the organization" and "discipline," including the Ministry, he is capable of flexible and calm judgment, such as when he restrains Torquil Travers, the Head of Magical Law Enforcement, when the latter takes a high-handed approach that doesn't shy away from force. However, he is also the type whose emotions easily show; he can get heated when he worries too much, when things don't go well, or when unexpected situations occur. Theseus's principle of action is his own sense of "justice," and he values "family" very deeply. For this reason, while he is often exasperated by his younger brother Newt—who dislikes belonging to organizations or groups and frequently causes trouble with those around him due to his handling of magical creatures—he still tries to look after him. To give an idea of how much, he sends letters to his brother while he's traveling, talks to him constantly to give advice within the Ministry, and even goes as far as seeking a hug; he cares for his much younger brother from the bottom of his heart. Sadly, to the essential Newt, he seems to be regarded as a bit of a nuisance (though Newt certainly doesn't hate him). He absolutely loves Newt.

It has a platypus-like appearance, characterized by a long, protruding snout and beak, and fluffy black fur. Their most well-known habit is their attraction to shiny metal objects and jewelry. Anything that glitters seems to be a target, and once found, they stuff it into a pouch on their belly that is seemingly inexhaustible. Their habit of searching for shiny things makes them excellent for treasure hunting if domesticated, and goblins often use Nifflers to find treasure buried deep underground.

Characterized by a body made of bark and twigs, reaching a maximum length of only 20cm. It has two arms and three legs. It is known among the wizarding world that they can easily pick locked latches.