Arvis is one of the few residents of Narshe to pick a side in the conflict. Narshe is a neutral town and most of the residents prefer that it stayed that way, but as miners have uncovered a frozen esper in the Narshe Mines, Arvis believes the Empire will attack the town anyway. He has grown disillusioned by unsuccessfully trying to convince the residents to side with the Returners, describing them as "too stubbornly independent".
When Terra Branford raids Narshe to obtain the frozen esper for the Empire, she blacks out and Arvis rescues her. He warns her to stay away from Narshe and the Empire and should find her own path, but she is amnesiac and cannot remember anything but her name. Arvis sends for Locke Cole, a renowned treasure hunter and Returner, to take her to the Returner Hideout to meet with Banon.
Terra, Banon, and Edgar Roni Figaro return to Narshe to visit Arvis and take a look at the frozen esper for themselves. Arvis decides to bring them to see the Elder of Narshe to convince him of the need for Narshe to join the Returners. The Elder hesitates but when Locke returns with news of an impending Imperial attack, Banon and the others help defend Narshe in the battle for the Frozen Esper. The attack convinces the Elder that war is inevitable, and that they need to ally with the Returners.
After a series of events, Arvis and Banon suggest a strategy for overthrowing the Empire. Terra would plead for the espers' help and have them attack Vector from the east while a coalition of Returners and Narshe guards, led by Arvis and Banon, would storm Vector from the north. The strategy works, but the espers go too far and decimate Vector. After Vector is occupied by the allied forces, Arvis is found in the city in a state of shock. What happens to him during the end of the world or in the World of Ruin is unknown, but he is never seen again after Vector is abandoned.
Arvis has its origins in the Old English language, it means "friend of the people".
- In the remakes from Dawn of Souls onwards Arvis is one of the default names the player can choose for the Monk job.
- The developers refuse to comment on Arvis's fate, with Hironobu Sakaguchi saying, "Use your imagination".