Cyrus, 19, put on heavy eye lashes, multi-coloured nail polish and leopard print and donned Minaj's signature pink lipstick at Sunset Boulevard, Oct 30, reports contactmusic.com.
Her actor fiance Liam Hemsworth dressed up like a unicorn.
Actor Zac Efron also attended the bash dressed up like a cowboy.
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Photos: Katrina Kaif, Parineeti Chopra, Shilpa Shetty's movie outing in Juhu
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Photos: Vaani Kapoor, Poonam Pandey, Sana Khan at fashion event
Photos: Rishi Kapoor, wife Neetu, daughter Riddhima at book launch