How did the dark glory wizard die?

In the Korean drama "Dark Glory", the wizard's psychology itself has a burden. Long-term use of magical drugs, coupled with sudden drop in temperature, excessive exercise, irregular diet and malnutrition, leads to sudden death.

"Dark Glory" tells the story of Wen Tongxun who suffered serious school violence in high school. He has been dormant for many years to make the perpetrators pay for their evil deeds. Wen Tongxun gambles all his life and launches a revenge plan.