Arlo always dreamed of entering the league, and spent a great deal of time watching the battles as he honed his own skills, yet each time he would try to make it in, his abilities were never quite enough to carry him into the roster. Feeling lost and defeated, he one day stumbled across a legend of the arena, Haliberton, who saw promise in the young Foil wielder. Becoming a popular newcomer in Season 2, Arlo has seen immediate success in the league after being taken under the tutelage of Haliberton.

Arlo is the middle child, in a family with three different children. Each was trained from an early age in a fencing style. Arlo was trained using a Foil. His older sibling Marlo was trained using an Épée. While the youngest of the three, Carlo was brought up on the Sabre. As the three grew up and trained together, Marlo and Carlo would find success in their fields, fighting in various different fencing tournaments and coming out on top with ease almost every time. Arlo however, struggled to keep up such a pace, and would often fall to stronger opponents.

Distraught by his lack of abilities compared to his siblings younger and older, Arlo decided one day that he would no longer participate in the local fencing competitions and he instead decided he would join The Arena. The three siblings were all quite aware of the Arena and its participants and battles, as they were televised all over. After witnessing the first Season, Arlo in particular was enamored by the different weaponry and fighting styles all meeting together like that. So, Arlo told his family what his plan was, to leave his home, and join the roster of the Arena, where his family could watch him win match after match. Unfortunately, his family did not quite believe him, not that he wouldn't leave, but that he could win, given his track record. Angered by this apparent lack of faith in his abilities, Arlo stormed from the home he grew up in, and went straight towards The Arena grounds. Immediately, Arlo would walk up to the registration desk and demand a chance to join. After being given the opportunity however, he would once more fall short and not meet the requirements to be able to join.

However, one person watching his test thought differently. Looking up at the blurring lights above as he was laying in defeat, Arlo suddenly saw a gauntlet covered hand reach out to him to help him up, and once Arlo wiped the tears of disappointment from his eyes, his expression shifted entirely from sadness to shock as he saw the one to help him up was Haliberton, a stoic, and tough fighter that was one of Arlo's favorites to watch from home. After some string pulling with the Arena Staff, Haliberton secured Arlo's spot on the roster, at the cost of Haliberton needing to sit out for the next Season to take time off to train him. It would be a long and gruelling several weeks of nonstop training and discipline building, but eventually, Arlo found himself growing stronger, faster and more skilled with his Foil passed down to him by his family. Eventually Haliberton felt Arlo was truly ready now for the Arena, and the two would return just in time for Season 2, with Arlo feeling like a whole new person.

Later on, as Arlo became more and more accustomed to life at the Arena facility, one day he noticed a brand new face at the registration desk, a woman who looked to be about his age, who was holding a weapon the likes of which he had not seen before. After approaching her and trying to introduce himself, he began to flounder as he realized she did not speak the language he does very well, nor did he understand hers. Thankfully however, Haliberton's past of travelling around, and his strict training as a child involved the need to learn multiple different languages, and he was able to act as a translator who revealed the woman's name was Tama. After their indirect conversation, the two became friends as they began to start trying to teach each other their own respective languages. But when the time arrived to form two person teams for the Season 3 Grand Ball Cup, Arlo knew he couldn't just abandon Haliberton, and he knew how good of a chance they might have to win together specifically. However, Tama would also end up meeting the Season 2 Champion, Finn, who she was a big fan of through her own watching of the battles, and fortunately for her, Finn just so happened to also know and speak the language she did, making the perfect teammate for the Season.

Despite the distance between them, and the competition, Arlo and Tama kept in contact and would meet together each night after the battles to learn about each other, their language, and cultures. For the Season 4 Boss Gauntlet however, the pair would be able to reunite for real, as Students under the Master, Haliberton.