It's near the very end of the series when InuYasha and the gang are trying to defeat Naraku and for like 7 episodes Naraku is in that HUGE barrier that's so powerful. Kohaku is with Sesshoumaru the whole time.
*Mt Hakurei Episode 111
episode 35
Episode 80: "Sesshomaru and the Abducted Rin"
in episode 9
It wasn't in an episode, it was in the 4th movie, Fire on the Mystic Island.
Because the shard is too powerful for the sword. Too much EVIL!
*Mt Hakurei Episode 111
Episode 49: Kohaku's Lost Memories There you go! -Miz
the third or fourth episode.
episode 35
No there is not,sorry
Yes he does, actually. In the final act he and his group, sesshomaru's group, Kohaku and I think maybe Koga help a little. Kinda hard to think they don't defeat him though.... Spoiler: (Sesshomaru gets a new arm and a new sword.)
It was episode 35 that Sesshomaru saved Rin.
*Sesshomaru Episode 35
Episode 80: "Sesshomaru and the Abducted Rin"
In episode 116. They are looking for rin who was kidnaped and jaken got off subject trying to talk to sesshomaru who was ignoring him at the time.
Shippo asks Sesshomaru to revive his friend in episode 126 of the anime series "Inuyasha." In this episode, titled "Transform Heartache into Courage," Shippo pleads with Sesshomaru to use Tenseiga to revive his friend, a young fox demon named Kōryū. Sesshomaru initially refuses, but eventually agrees to help Shippo after witnessing his determination and loyalty to his friend.