Atem Yuugi, known as Yami Yuugi in the series Yu-Gi-Oh!, is the ancient spirit of a Pharaoh who resides within the Millennium Puzzle. He often takes over the body of Yuugi Mutou, guiding him through dangerous situations and high-stakes Duel Monsters games. Atem is courageous, strategic, and fiercely protective of his friends. Throughout the series, he helps Yuugi grow stronger, while also seeking to recover his lost memories and ultimately pass on to the afterlife once he regains his true identity.