Doctor Amnesiac, but not completely amnesiac

"Dr. Kal'tsit, are doctors in the past really that scary?"
Looking at the old guys one after another making new deals with the doctor with expressions of fear and excitement, Amiya asked in confusion.
"Yeah...but that was a long time ago."
Kal'tsit will not tell little Amiya the truth, but if you really want to know, you might as well turn the clock back twenty years.
At that time, the Witch King of Leithania fell from the tower, and all the electors were ready to make a move - who helped the twin queens to sit firmly on the throne?
At that time, the late emperor of Ursus had passed away four years ago, but the empire was still paying for his military gamble - who helped them get out of the haze again?
At that time, the conflict between Casimir's knights and merchants reached its peak, and the two sides were just one step away from fighting - who helped them suppress their raging anger?
He formed alliances among the various countries of Terra and used people's ambitions to gain the greatest benefits for himself - until the tower that reaches the sky pierced through the throne of God.
"Actually, I really just want to save the world."
——A sunny and warm doctor said with a smile.