Needs More Whammy Bar
Needs More Whammy Bar is an achievement in Halo: The Master Chief Collection. It is unlocked by completing the level Regret with the Prophet Birthday Party skull active. The achievement is worth 5 gamerpoints and can be unlocked on any difficulty.
The achievement's name is a reference to the fact that the Prophet Birthday Party skull causes each punch the player lands on the Prophet of Regret to be accompanied by an electric guitar lick.