There's a recent Donghua I've been watching which revolves around a mercenary who was a former war hero turned slave that was paid and freed by one of the five chiefains in a city-state area existing outside of the Murim Empire. Him and his son go on several bounties in an attempt to pay for his debt even though the man who freed him doesn't ask for anything in return. Through all his bounties, he continues to serve justice and atone for his sins.

Watch it here

Spoiler:

https://lmanime.com/blades-of-the-guardians/

There's also a live action adaptation of this.
Watch it here

Spoiler:

https://ok.ru/video/15344371370594