The Witcher: Grinding Experience Starting as a Wolf School Witcher

In 1228, a veteran Witcher player transmigrated into the body of a Witcher apprentice named Arwen Thyssen. That year, the northern kingdoms were busy expanding their territories, and the borders were rife with war and conflict. Monsters lurked everywhere in the mountains and wilderness. What should have been the most active period for Witchers was instead destroyed by the book *Freaks*. Fortunately, Arwen awakened a skill proficiency system, allowing him to obtain mutants by killing monsters. [Kill a Water Ghost, obtain 100% Water Ghost Mutant, gain the talent Underwater Breathing (White)] [Kill a Dragon, obtain 100% Dragon Mutant, gain the talent Dragon's Eye (Orange)] What if you can't beat the monsters? Grind experience! [Apprentice Swordsmanship lv1 → Apprentice Swordsmanship LvMax, gain the talent Blade Perception (White)] [Starry Sky Meditation lv1 → Starry Sky Meditation LvMax, gain the talent Avatar to Godhood (Rainbow)]... Years later, the North-South War began, and the northern kingdoms were defeated. "The one who comes is the white flame dancing before the enemy's grave, Emperor Emhyr var Emris of Nilfgaard." Emperor Emhyr slightly raised his head, looking at the black-haired, golden-eyed man sitting high on the Iron Throne across the Pontal River. The herald's voice rang out again. "Before you stands His Majesty Alwin Thyssen, mentor of the Witcher Order, Dragon Slayer, terminator of the White Frost Prophecy, peacemaker of races, outstanding graduate of Aretusa, member of the Association of Talents and Arts, and ruler of the Kovir Empire." (P.S. This is a fanfiction of Witcher and Wizardry; reading it is not necessary for those unfamiliar with the original works.)