He was trained in martial arts since early childhood by a monk from Biron Monastery which is why even though he is only fourteen years old, he is still very muscular. He wields the Ra-Seru Meta, which allows him to fight the Mist controlled Seru and activate the Genesis Trees to drive away the Mist and reach Mist Generators.
He is naïve in adult matters such as love which made it difficult in understanding that his childhood friend Mei had a big crush on him, though at the end of the game, players could choose to have them get together. As he journeys and saves towns, he becomes more and more famous however, which gets him more admirers, and even little girls develop a crush on him.
Vahn has a strong sense of justice and hates to see people suffer which is what made him start his journey. He also has a little sister whom is very mature for her age.