Baek Sung-hyun

as Cheol-soo's uncle

as Choi U-ri

as Kim Jong-hyun

as Kim Yeon

as King Mokjong

as Jang Kyung Joon

as Kim Yeong Kwang

as [Lion Hearts FC]

as Sung-doo

as Do Hak Young [Cable Man]

as Shim Dae-Sik

as Park Tae-seong

as Hyun-woo

as Lee Young-gook

as Kim Byung Chul

as Goo-rim

as Park Hyun-soo (27)

as Chun Ji Woon

as Park Hyun-woo

as adult Choi Jung Woo

as Kang Byung-jin

as Eun-hyeok

as Gil Choong-shik

as Prince Dowon/Crown Prince Ui-kyung

as Park Mu-yeol

as Goo Dae Gu

as Kyeon Ja

as Kang Byung-jin

as Baek Jung-goo

as Self

as Joon-oh

as Yoon Jung-won

as young Gungbok

as Cha Song Ju (Young)

as Ji-oh

as Ko Yeon-mu