Yoriichi Type Zero is destroyed at the end of Tanjiro's training, but a sword from over 300 years ago appears from inside. Kotetsu gives Tanjiro the sword, however it is badly rusted. At that moment, Haganezuka appears and takes the sword with him to perform a grueling whetting process handed down within his family line. Meanwhile the presence of demons are inching closer to the village...
That polishing art of his is so brutal,
some people have even died, and that worries me.
فنّ الصّقل خاصّته غاشم جدًّا لدرجة
.أنّ هنالك من مات جرّاءه وذلك ما يقلقني
Aber ich mach mir schon Sorgen.
Que ese método de pulido es muy extremo
y que ha muerto gente. Me preocupa.
Me han contado que esa técnica de pulido
Mais ça m’inquiète,
car des gens sont morts
उनकी पॉलिशिंग आर्ट इतनी क्रूर है
कि कुछ लोग मारे जा चुके हैं,
A quanto pare, la tecnica necessaria è impegnativa
Essa técnica de polimento é tão brutal 
que algumas pessoas morreram. Estou preocupado.
Метод такой изнурительный,
что даже сгубил несколько человек!