Katy Perry sings.
`` Dark Horse '' is a song recorded by American singer Katy Perry featuring rapper Juicy J . Katheryn Elizabeth Hudson ( born October 25 , 1984 ) , known professionally as Katy Perry , is an American singer and songwriter . Her fourth album , Prism , was released in 2013 , and is influenced by pop and dance . `` Part of Me '' is a song by American singer Katy Perry , released as the lead single from Teenage Dream : The Complete Confection . Prism is the fourth studio album by American singer Katy Perry .