Marcus Damon (Japanese name: Masaru Daimon) is the main protagonist in Digimon Data Squad. His partner digimon is Agumon. He is also called "Boss" by Agumon. Marcus's rival is Kouki and his archenemy is Akihiro Kurata.
He is the first human lead of any Digimon serial, excluding C'mon Digimon, that doesn't wear goggles. Marcus is also the first and only human protagonist to physically hurt Digimon on a regular basis. He was going to become the heroes instead.
In the Japanese version, when referring to himself, Masaru adds "-sama" (様) onto his name.
Marcus's birthday, April 2, is the same day Digimon Savers started in Japan.
Marcus is a tall teenage boy with lightly tanned skin, shoulder length auburn hair and olive green eyes. His hair is usually tied back in a half-ponytail, with bangs framing the sides of his face. Marcus's civilian attire consists of a white shirt under an unbuttoned red shirt, blue jeans, and red sneakers with white laces and soles. He wears a rectangular silver pendant on a white string, given to him by his father.
His DATS uniform consists of a dark blue-and-white half-sleeve jacket with two yellow upside down triangle marks on the chest, a red jumpsuit with a partially white collar underneath, a light grey belt, and white and dark blue knee-high boots. He wears his pendant around his neck along with his Digivice.
While he is at school, Marcus wears the Ootori Municipal Middle School uniform, consisting of a red blazer over a white button-up shirt, a grey tie, grey pants and black shoes.
After he returns from the and has his memory erased, he begins wearing a black tank top, a red-and-white vest, khaki jeans with fake suspenders, black buckled wrist bands, and red sneakers with black laces and soles, as well as his pendant.
As a four-year-old boy, Marcus's hair is short, messy and parted in the middle. He wears an orange short-sleeved hoodie, light blue jean shorts, white socks, and red shoes with grey laces and soles. Later, his father gives him his pendant.
A junior high student who prefers to fight over a 3rd serving of rice. When he meets ones who looks strong, he can't help but challenge them to a fight. After he met and fought against an Agumon one day, they find mutual understanding and become Partners. Because of his latent powers which allowed Agumon to evolve, he joins DATS in search of stronger opponents. Even though Marcus is the son of the No.1 authority on Digimon research, Professor Spencer Damon, he is completely hopeless with computers and machines, and he usually ends up breaking or destroying them.
Marcus is the kind of guy who would rather settle a dispute with his fists. He is loud and arrogant, and often rude and confrontational. However, his heart is in the right place. He is a caring and loyal friend, son and brother, who would protect his loved ones no matter what. He has a soft spot for children, stemming from his strong connection to his younger sister, Kristy.
Marcus isn't a good student, as he would rather fight or eat than study.
Marcus would usually pick fights. Hot-blooded, impulsive and doesn't think things through, he shares this trait with Agumon. However, when asked by Thomas about his motive for being in DATS and learning about his dad's past, Marcus learns there are other things to do than fighting. He doesn't give up or back down and wants to fight till the bitter end.
He learns there are battles he can't win all the time and knows that if you leave now, you can always fight another time... but, it has to hit him pretty hard to make him do that. He can also be eager to learn new things... just as long as said 'new things' are easy for him to understand.
Marcus's main personality is fighting and he gets cocky sometimes. To Digivolve his partner, Agumon, he must use his fist to punch an evil Digimon to gain data in his Digivice. He is consider as a hot headed fourteen year old student, who loves to fight, which he considers himself to be an "ultimate fighter". He also does street fighting, and in his own way. He also dislikes taking exams and is afraid of Yoshi when she gets extremely angry. He does care about his little sister and tries to protect her at any cost.
Marcus was born to Spencer and Sarah Damon. When he was a child, he would play catch with his father. He would also secretly look at butterflies with his father. Marcus did not know that his father worked for Dats, and was tasked to look for the Digital World. Marcus was also taught to ride a bike, but hit his head in the process. Which resulted for him to cry, but his father told him that everyone fails on the first try. When his father was leaving for the Digital World, Marcus who looked at his pendent around his neck then happily looked at his father decided to wave goodbye to him and told him to come back soon.
Sarah told Keenan, that when Marcus was little. He would usually lay on the rooftop, thinking on things that were stressing him out. He would usually tell his mother, about it later on though. He also cares about his little sister.
Marcus lives with his mother, Sarah, and younger sister, Kristy. He meets and fights Agumon in the first episode of the series. When the fight ends in a draw, Agumon agrees to become his partner. Soon afterwards he's recruited as a member of DATS. As Marcus' partner, Agumon idolizes him and refers to him as his boss. Marcus is one of the few shown to fight Digimon by himself, though he still counts on Agumon's help to fight the stronger opponents. Even though others can evoke their DNA charges by themselves, Marcus must connect a punch on an enemy to do so, subsequently using it to digivolve Agumon.
Before leaving the human world to confront Merukimon, Marcus gained an alternate motive for going, which was to find his father Spencer, who he believes to still be alive, and bring him back home. However, the only clue he has about his whereabouts was given by Merukimon himself, who revealed to be a friend of Spencer and said he set off in search for King Drasil, the God of the Digital World, in his effort to build a co-existence between humans and Digimon. Marcus only learned other things about Spencer when he and his friends reached ElDradimon and learned that the people there have a debt of gratitude with him for helping the city years ago. They swore to protect the city from Kurata's army, but, in the end, there was little that they could do to prevent ElDradimon from being destroyed. Marcus caught Agumon after reverting to egg form.
Another moment of despair occurred when Thomas, for personal reasons, was forced to side with Kurata, and he had to fight him. During the battle between ShineGreymon and MirageGaogamon, Like Tai and Takato, Marcus' anger triggered the dark digisoul inside himself, dark digivolving his partner to a corrupt and rampaging version of ShineGreymon Burst Mode called "ShineGreymon Ruin Mode". After finally stopping him, he returned to a Digi-egg state, but it did not take long for Agumon to return to life and digivolve to ShineGreymon once more. Imbued by the determination to protect those that he loved dearly, his friends, his fellow DATS members who were close friends akin to family and, of course, his family themselves, Marcus was able to bring him properly to ShineGreymon Burst Mode to fight Kurata Belphemon. After Belphemon's defeat, Marcus Digivise the DATS team faced a threat even greater when King Drasil decides to wipe out the human world to end the struggle between the worlds once and for all, with the help of the Royal Knights. Marcus confronts King Drasil himself, just to discover that he is, in fact, Spencer Damon, his long lost father. After being rescued by Kentaurusmon, Marcus intends to go back to the Digital World to confront his father.
After meeting up with Gotsumon again, Marcus and Agumon faced off against Craniamon once more, where the Geogrey Sword actually broke. With help from the others, they were permitted to see King Drasil. Upon reaching him, Marcus fought his father, but couldn't land a hit. However, after hearing his father's disembodied voice, and with help from the Digimon, Marcus was able to connect a hit. BanchoLeomon appeared to help Marcus, only to reveal that he was holding the real Spencer inside his body before grabbing King Drasil and telling Marcus to kill them both. With severe hesitation, Marcus ordered ShineGreymon to unleash the attack that took them out. Just before the attack hits, Spencer thanks Marcus. With King Drasil seemingly defeated, and the World Tree destroyed, everything seems like it's over. However, King Drasil's true form appears, and it took a hit from Marcus to convince it not to continue and rest to see the results of a human and Digimon co-existence, reviving Spencer. In the series epilogue, Marcus decides to stay in the Digital World and help Agumon keep the riff raff in line and out of trouble.
- He is the only main character in a particular season to not wear goggles.
- When he was young, he is voiced by Debi Mae West is best known voicing as Kotemon from Digimon Frontier: Island of Lost Digimon.
- Marcus Damon is the same age as Thomas H. Norstein.
- His English Voice Actor, Quinton Flynn is best known voicing as Iruka Umino from Naruto/Naruto Shippuden and Kon from Bleach.