The Murky Stream

Set in a tumultuous period where the political scene is murky and various people fought to gain power and the throne, the young king will do anything to strengthen his shaky position in court. His childhood friend Baek Rok leads a secret military force loyal to the king, called the "Black Cloud Swords".
Baek Rok lives for his king, his brother Baek Kyul and his lover Jung Yeon, but when his ambitious brother betrays him and leads him into a trap, he finds himself on the run. He becomes a slave and gladiator, eventually returning to Joseon to seek revenge

Both are period dramas where male lead survives as a lawless person and second male lead is a government official. Both dramas are rough and brutal which shows how inequality in society destroys it.

Both of those dramas are similar, deciphering into the Joseon Era and explaining the male lead as they have the same rags to riches journey with rising to power and how they became to be.