Ending 19 is unlocked by completing Greedier Mode, defeating Ultra Greedier.Ending 18 is unlocked by completing Greed Mode, defeating Ultra Greed.Ending 17 is unlocked by completing ?, defeating Hush, for the first time.Ending 16 is unlocked by defeating Mega Satan.Ending 15 is unlocked by completing Dark Room, defeating The Lamb.Ending 14 is unlocked by completing Chest, defeating ?.Ending 13 is unlocked by completing Cathedral, defeating Isaac.Ending 12 is unlocked by completing Sheol, defeating Satan.Endings 1-11 are unlocked by defeating Mom's Heart in Womb (or its variants) for the first 11 times.Epilogue is available after defeating Mom in Depths (or its variants) for the first time.The credits are played after any ending.They can be viewed in the 'stats' section of the menu. They can be unlocked by killing the boss at the end of chapters 3-6. There are 16 endings in Rebirth, with 2 more added in Afterbirth, 2 added in Afterbirth+, and another 2 added in Repentance. They are all different and generally depend on the player's route through the game. Endings are cutscenes that play at the end of each completed run.
