After Playing the Fool for Eight Years, I Own the Whole Capital

The instant special forces king Xiao Mohan completes his mission, the woman he loves, Su Qingcheng, sends him to hell with a single injection of poison. When he opens his eyes again, he's become the eight-year-old, intellectually disabled legitimate eldest son of the Prince of Zhenbei's household. The first thing he sees is his concubine stepmother, Liu Ruyan, kindly offering him a bowl of medicine.