Most of the songs were written and recorded by Tyler in December 2009 and released on Bastard the same month. Tyler produced most of the mixtape using FL Studio.
Bastard features Tyler speaking to a character named Dr. TC, who acts as Tyler's therapist and guidance counselor. The title track contains Dr. TC hinting that Tyler will be releasing his upcoming album, called Goblin (2011), to be an additional session with him, stating that there would be three sessions. Both songs "Odd Toddlers" and "Slow It Down" were previously released on The Odd Future Tape (2008). The chopped and screwed version (which was hosted by fellow rapper and label-mate Mike G) was released for free online. The mixtape was later re-released as part of the one-year anniversary, with the song "Session" being updated, and replaced Brandun DeShay's verse, with a new one by Mike G, after the dissension between Tyler and DeShay. The project is now made available on Odd Future's online music store, with DeShay's vocals returning to that same track. Tyler later announced intended plans on re-releasing Bastard in a remastered physical form through Odd Future Records. However, since this announcement, nothing has materialized.
Bastard received critical acclaim, and was ranked at number 32 on Pitchfork's list of the Top 50 Albums of 2010, while the single "French!" was ranked at number 61 on Pitchfork Media's list of the Top 100 Tracks of 2010.
On December 25, 2010, one year after the album's initial release, it was re-released with brandUn DeShay's verse on "Session" replaced by a verse from Mike G. However, in 2012, the album was re-uploaded to the official Odd Future website with both DeShay and Mike G credited on the song.
"VCR" contains uncredited vocals from Earl Sweatshirt
"Inglorious" contains uncredited vocals from Hodgy Beats
"Odd Toddlers" contains a sample from "Huit Octobre 1971" performed by Cortex