Kim Yun-seong

Kim Yun-seong in his early 30's who discovered he has gained Trace abilities. His Trace power is his iron legs, which allow to use powerful kicks that destroy walls and make him leap great distances. He is the leader of the Beggar Team.

Trace
A salaryman in his 30s, Kim Yun-seong was a man with a perfect life: a job, a loving wife, and a daughter. All this changes when one day he turns into a trace with powerful legs. Being a law-abiding citizen, he decides to legally register as a trace, rather than hide his identity.

After that he is separated from his family who are taken to a trace facility where the family of the traces are taken. When he is not able to contact them he goes to the facility to see his family where he is stopped by a group of trace guards and chased where he meets Jeong Hee-sub who is also a trace trying to get into the facility. They join and form a team, informally called Trace Circus, and recruit other members. They succeed in entering the facility where Kim Yun-seong finds the family of the traces who are brought there are used for experimental purposes and killed.

After the mission is done and the evidence sent to press. Trace Circus brakes up and Yun-seong returns to be being a begger. Upon hearing the news about the break-in on the news but not seeing any evidence of experiments done on Traces. Yun-seong brings the team together again and vows that Hee-sub's death would not be in vain as he and his team attempt to expose what the government as done to his family and others.

By the end of season 1 Yun-seong is one of the most powerful traces on the planet. He's also considered a dangerous criminal by many.

Trace 1.5
During the events of Trace 1.5 it is revealed by Han Si-Hyun that during the events of Volume 7 The Last Day Yun-seong temporarily turned into a trouble.