Character

There are eleven playable characters in The Binding of Isaac: Rebirth with three extra characters in the DLCs. Five of these characters (Isaac, Magdalene, Cain, Judas, and ???/Blue Baby) came with the original Binding of Isaac, while two additional characters (Eve and Samson) were added later. Eve was added in the Binding of Isaac's Halloween Update, while Samson was added in The Wrath of the Lamb expansion. Rebirth contains four new characters (Azazel, Lazarus, Eden, and The Lost). In the Afterbirth expansion for Rebirth, one new character (Lilith) was added, plus one more character via an update (Keeper). In the Afterbirth † expansion for Rebirth one character (Apollyon) was added. Each character starts with different stats and abilities that give them their own unique play style.

Each character's progress can be gauged by checking their Completion Marks.

Unlocking
Each character is unlocked by accomplishing a certain task in the game. The unlock requirements are as follows:

Trivia

 * One common theory (which was confirmed by Edmund) is that all characters are different forms of Isaac himself. This theory suggests that every character is a creation of Isaac's imagination which he assumes the personality and appearance of when playing as them. Most characters represent different issues that Isaac believes he has, while ??? is Isaac after dying by suffocation inside The Chest, Azazel is who Isaac sees himself as, and The Lost is Isaac's wandering soul (which can be seen upon dying).
 * Additionally, Keeper is Isaac's desiccated corpse, as evidenced by Ending 18.

Personnages