S1, E3: Demimeramon shows up in the human world, spreading fire and creating havoc. Marcus and Agumon try to fight him, but Agumon's fire attacks do nothing and Marcus' punches go right through him. Demimeramon easily escapes them. But Thomas Norstein and his Digimon, Gaomon show up and get the job done flawlessly. Thomas is not only of royal descent, but a genius who has been away on another DATS assignment. Marcus is quickly threatened by Thomas and the two square off. Thomas tells Sampson that he believes Marcus has no place in DATS. Marcus challenges Thomas to a fight in the boxing ring, and is initially defeated. But Marcus doesn't give up and fights to a draw. Suddenly, Demimeramon is back and has multiplied several times over. Thomas is dispatched to deal with the problem leaving Marcus to brood. But as Marcus walks off his anger, he begins to realize he may not be as great a fighter as he thought he was. He runs into the old man again, who teaches him a lesson about perseverance, and fighting fire with fire as an example. Just then more Demimeramon attack again, but Thomas is too far away to do battle. Marcus defies orders and confronts the threat himself. Since he can't land a punch against Demimeramon, he forces him to digivolve into Meramon. Then he hits him with his fist and activates his DNA! Agumon digivolves to Geogreymon and defeats Meramon. Back at DATS, Sampson has had enough of the Marcus and Thomas fighting. He makes the two work together as a team from now on.