Inu-Yasha: Swords Of Destiny (V.12)

"A sword can live or die, depending on its master."

An old demon named Totosai comes asking to see the Tetsusaiga. Claiming to have forged the sword for Inu-Yasha's father, Totosai begins a series of tests to determine if Inu-Yasha is worthy of the blade. When Sesshomaru appears, demanding that Totosai forge a new sword for him, Inu-Yasha must come to Totosai's aid - but not before learning that only by mastering the powerful "Wind Scar" technique can Inu-Yasha defeat his brother.

Episode 034. "Tetsusaiga and Tenseiga"
Episode 035. "The True Owner of the Great Sword"
Episode 036. "Kagome Kidnapped by Koga, the Wolf-Demon"