In Doctor Strange, the Cloak of Levitation took on the aspect of an animal sidekick. It was like it was the long-lost brother of Aladdin’s Magic Carpet. And while the Cloak’s personality came from CGI, its design came from Alexandra Byrne.
Source: io9 – A ‘Graveyard of Red Fabric’ Went Into the Creation of Doctor Strange’s Cloak of Levitation