Yes, Sensei
Yes, Sensei is a Multiplayer Achievement in Halo: Reach. The achievement is awarded if a player earns a First Strike medal in a Matchmaking game.[1]
Trivia
The achievement's name is a reference to the 1984 film The Karate Kid, where the evil Cobra Kai dojo advocating striking first, and striking without mercy.[2] Sensei means both "teacher" and "first strike" in Japanese.[3]