Demon Slayer: Kimetsu no Yaiba Swordsmith Village Arc Episode 3 SUB at Gogoanime

Synopsis: 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 is inching closer to the village... (Source: Crunchyroll)