16. Kendrick Lamar, 'Untitled Unmastered'
This addendum to Kendrick Lamar's To Pimp a Butterfly is the best rap demo collection since Nas' The Lost Tapes. It's as ambitious and orchestral as that 2015 insta-classic, but its lack of finishing touches – some of the tracks like "Untitled 07" burble with tape hiss and studio chatter – results in an appealingly loose feel. There are some surprises, like when Lamar's voice suddenly gives way to Jay Rock on "Untitled 05," or when CeeLo Green begins to croon on "Untitled 06." "Untitled 08," a G-funk throwback co-produced by Thundercat and Mono/Poly that's alternately known as "Blue Faces," would have been a fantastic B-side to "King Kunta" if Lamar had issued the latter as a 45 rpm single. Still, inclusion on this superior epilogue to one of the best albums of the decade is more than enough. M.R.