Kanye West ft. Kid Cudi – “Welcome to Heartbreak” (2009)
While he was working on 808′s in Hawaii, Kanye pulled together a wildly diverse crew of collaborators – from Mr. Hudson to Young Jeezy to Tony Williams – to help him create his first concept album on which he’d be singing. At the time, Cudi was little more than buzzing artist who’d put out one great mixtape in A Kid Named Cudi, but he jumped right into the opportunity and provided vocals and writing assistance on several songs. The best of the collabs is “Welcome to Heartbreak,” on which Cudi helps ‘Ye explore his humanity, and the track “humanizes West in a way rappers aren’t supposed to be humanized,” according to PopMatters.