With the release of the Afterbirth expansion in October 2015, there was a new secret, but this one was not so easily datamined. However, dataminers quickly discovered his existence by looking at the game code and The Lost became common knowledge in a few days, much to the disappointment of the game creators. When The Binding of Isaac: Rebirth was released in November 2014, a super-secret character called The Lost was included, with a complex unlocking mechanism that was designed to be a community scavenger hunt - an ARG of its own.
