Webmost notoriously about hantengu's unique power is that he takes advantage of the traditional method of decapitation to kill a demon, as beheading hantengu's.
Webonly appears when hantengu feels he's at his most desperate with a fusion of his four main emotions, acting as some sort of guardian entity towards him and accussing hantengu's.
Webhantengu's blood demon art is rooted in emotional manipulation, where the various emotions that arise from his psyche are manifested as younger clones of his.
Webno other demon has had so many forms and manifestations, making it clear that hantengu is worthy of his spot as the upper four demon in demon slayer.
Webhantengu has six emotions living within him:
Sekido (anger), karaku (pleasure), aizetsu (sorrow), urogi (joy), zohakuten (hatred), and urami.
This form has of a tengu fan that the demon uses to create powerful gusts of wind that can decimate buildings and blow people away long.
Sekido, karaku, aizetsu, urogi, zohakuten, and urami.
Through tanjiro’s encounter with hantengu, he learns that beheading the upper.