Pengbaesu - heavy infantry
This could be new korean unit to recrute in the castle by Koreans.They need some unique ,human military unit" i think.
The Pengbaesu was an infantry unit that accounted for a significant portion of the early Joseon army . In the 15th year of King Taejong’s reign (1415), it was implemented as the center of a miscellaneous position system consisting of a captain and a deputy captain, and was renamed Pengbae in the 13th year of King Sejo’s reign (1467). They were a shield-sword unit armed with a Pengbae (small round shield , similar to the Western round shield ) and swords as their main weapons for close combat, and they were specialized in close combat. It is presumed that their basic tactic was to form a square and fight.