Miley Cyrus dressed as Nicki Minaj for her annual Halloween party, which she threw at Beacher’s Madhouse in LA’s Hollywood Roosevelt on Tuesday. The bash came complete with a mini Mike Myers, four live goats and Miley’s mother, Tish, dressed as a skeleton. Also there were Zac Efron as a “Brokeback Mountain” cowboy with actor Ryan Rottman, Miley’s fiancé Liam Hemsworth (in a unicorn costume) and Pharrell Williams, who came as himself. One insider told us, “Miley was on the stage dancing like crazy. The guest list was tight and all guests had to sign confidentiality agreements and check their cellphones.” We’re told the crew went back to Miley’s house and continued celebrating all night.