In his past life, Desir only has enough mana to qualify as a mage of the First Circle. However, after being soul-bound to the Crest of Toa he got from a Shadow World, he has enough mana to become a mage of the Third Circle.
While only a mage of the Third Circle, he managed to become one of the six people who survived the Shadow Labyrinth. He also highly respected by the other five members and gaining praise from Zod Exarion, who was the one and only Seventh Circle magician and known as the strongest magician..
Despite being a lower-level circle magician, Desir’s main fighting style revolves around Analytical Magic which can be used to hack and cancel the magic used by other mages. He does this with such speed and efficiency that every mage he meets will be hard-pressed against him. Even Zod Exarion admits that when it comes to spell analysis and computation speed, Desir is above him.
Desir was skilled enough that he could calculate the thousands of spells inside the magic artifact that was used by Crow Mask during their fight.
While in the Shadow Labyrinth, one of his companions, an Esteban named Donovan Asylan told Desir that while he is a great mage, his body was weak. So Donovan took upon himself to teach Desir martial arts during their time in the Shadow Labyrinth. Desir became proficient in close combat thanks to that.
Magic Gem Enchanting
Normally, the mana inside a magic gem can only be utilized through a very special method that can extract the mana without dispersing it. Desir learned a skill which allows him to directly resonate with magic gems and use their mana for his own spells. Thanks to this, he can use magic spells beyond his circle class.
A separate form magic that is different from the magic that is usually casted by mages. It is the magic that directly affects mana that is casted in the language of the dragons. Using this magic can lead to incredible spells but will also inflict repercussions on his body. Desir later learns to combine this magic with the more common type of magic. It creates a powerful magic, however with a great amount of mana usage.
Desir has always been weaker than most of his opponents. Yet he survived all the way to the end of the Shadow Labyrinth. Everything he has experienced has culminated inside of him an incredible battle sense where he uses wits and tactics to take control of every battle he is in.
In this way, he was able to fight on par against the Third Circle Magic Swordsman Adjest and against the Sixth Circle Crow Mask and still defeat them. He once told Adjest about how his fighting style required a lot of forethought and scheming.