Six Flying Dragons

Han Gu-yeong

Yi Seong-gye (later King Taejo)

Sungkyunkwan student

Yi Bang-gan (later Grand Prince Hoean), Yi Seong-gye's fourth son Kim Sang-woo as young Yi Bang-gan

Gannan/Yeon-hyang, Boon-yi's mother

Young Yeon-hee

Ahn-won

Poeun Jeong Mong-ju

Gil Tae-mi/Gil Sun-mi

Sambong Jeong Do-jeon

Min Da-kyung (later Queen Wongyeong), Yi Bang-won's wife

Yi Ja-chun, Yi Seong-gye's father (cameo)

Cheok In-gwang, Cheok Sa-gwang's brother

Sungkyunkwan student

Yi In-gyeom

Cho-young

Boon-yi Lee Re as young Boon-yi Yoon Yoo-sun as old Boon-yi (cameo)

Yeon-hee Park Si-eun as young Yeon-hee

Yoon Rang/Cheok Sa-gwang

Yi Bang-seok (ko) (later Crown Prince Uian), Yi Seong-gye's eighth son Lee Seung-woo as young Yi Bang-seok

Myo-sang, Moo-hyul's grandmother

Hwang Hŭi

Young Boon-yi

Hojeong Ha Ryun

Hong In-bang

King Gongyang

Young Moo-hyul

Teacher Yooksan

Old Boon-yi (cameo)

Yi Ji-ran (ko), Yi Seong-gye's sworn brother

Gap-boon Kwak Ji-hye as young Gap-boon

Jo Min-su (ko)

Heo Kang/Yi Shin-jeok

Jang Sam-bong

Hong Dae-hong, Moo-hyul's martial arts teacher

Sagok Jo Mal-saeng (ko)

Yi Bang-ji, the best swordsman in the Three Kingdoms Yoon Chan-young as young Ddang-sae

Yi Do (later King Sejong the Great), Yi Bang-won's third son

Jo So-saeng (ko)

Hong Ryun (ko)

Yi Bang-u (later Grand Prince Jinan), Yi Seong-gye's first son

Heuk-cheop Seon-hwa

Moo-hyul, the best swordsman in Joseon Baek Seung-hwan as young Moo-hyul

Madam Kang (later Queen Sindeok), Yi Seong-gye's second wife