Episode 18

Naraku and Sesshomaru Join Forces is the eighteenth episode of the InuYasha anime. It first aired in Japan on March 5, 2001.

Plot
Sesshomaru receives a human arm with a Shikon Jewel shard embedded in it from Naraku as a means to wield the Tessaiga and destroy InuYasha. Miroku discovers that his wind tunnel can be inhibited by the Saimyōshō, the poisonous wasps from hell.

Trivia

 * This is the first time the Wind Scar was ever used in the series.