The Binding of Isaac

The Binding of Isaac

Developers: Edmund McMillen, Florian Himsl
Publisher: Edmund McMillen
Platform: Windows
Released internationally: September 28, 2011

This game has unused areas.
This game has unused graphics.
This game has unused items.
This game has unused sounds.
This game has unused text.

This game has a bugs page

The Binding of Isaac is the result of putting The Legend of Zelda, Smash TV, a roguelike, and a couple of dead baby jokes into a blender...and hitting Liquefy.

An expansion pack, Wrath of the Lamb, added more enemies, more levels, more items, more dungeon features, more bosses, more unused content, and more bugs. A little later after that came another expansion pack, 'Eternal Edition', that added some more stuff.

Three years after release, a remake of the game was released, titled The Binding of Isaac: Rebirth.

Sub-Pages

Bugs

Unused Graphics

A door leading to a spiraling staircase downwards. Could've possibly been an early versin of the trap doors used to travel from floor to floor in the final game.

Unused Items

Pumpkin Mask

The Pumpkin Mask

The Pumpkin Mask is an active item that was intended to be dropped by Krampus. It was supposed to shoot a Brimstone beam in four directions, but was later replaced with A Lump of Coal before the Halloween update was released. You're able to view the sprite by finding an undefined item, or hacking the item itself in. Its properties have been replaced with A Lump of Coal's.

An item with a similar effect, Head of Krampus, is obtainable in Rebirth.

Unused Enemies

Unused Fly Enemy

An enemy resembling a Pooter isn't used in any capacity. It might've been an earlier version or a new enemy altogether. How it might've behaved is unclear.

Unused	Used

Unused Sounds

The Binding of Isaac features a number of unused sounds. A good amount of them are alternates or retakes of used sounds or sounds reused from Edmund McMillen's prior works, particularly Super Meat Boy.

Name	Sound	Comments
boss2intro_remote_alarm.wav		A very grating buzzing alarm noise. Seems like it would've introduced a boss during the versus screen.
Bulb_Flash_0.wav		A sound involving a lightbulb. Much later, this would be used for the death sound of Bulbs, an enemy introduced in Repentance.
Bulb_Flash_1.wav		Another take on the lightbulb sound; see above.
Bullet_Shot0.wav		A bullet being fired. Resembles a sound the Blaster enemy appearing in Antibirth and later Repentance uses.
Bullet_Shot1.wav		Another take on the bullet shot sound; see above.
bum shootoff.wav		A duplicate of Bullet_Shot1.wav. The filename is interesting...would the Beggars be getting into gang wars?
fetus_flyingwhoosh.wav		An intense whooshing sound. The "fetus" part of the filename may be referring to Dr. Fetus, the antagonist of Super Meat Boy.
Fetus_Whistle.wav		A quick tongue-whistling sound. See above for the "fetus" part.
Monster_Grunt_3_A.wav		A low, rumbling monster grunt.
Monster_Grunt_3_B.wav		An alternate take on the above sound.
Monster_Yell_B_3.wav		A particularly guttural sound of a monster yelling.
Monster_Yell_B_4.wav		Another yell.
Monster_Yell_B_6.wav		A more subdued yell.
pillgoodeffect.mp3		An alternate take on the "good pill effect" sound effect used in the game.
pillpickup.mp3		A sound that might've played when you picked up a pill.
Powerup_Zelda_Headlift.mp3		A sound parodying the iconic "item get" jingle as heard in The Legend of Zelda (hence the name). Likely would've played when Isaac gets an item and holds it above his head.
Retro_keypickup.wav		A small positive retro beep. Perhaps an earlier version of the game's final key pickup sound.
Rocket_Launch.wav		A high-pitched laser-sight like noise that leads into the fiery sound of a rocket being launched. Perhaps could've been used with the Epic Fetus item. A very similar sound was implemented later with the rocket-firing effect of the Rocket in a Jar item first introduced in Antibirth and then appearing in Repentance.

Unused Text

A number of curious text entries can be found in the game that don't see any use. Interestingly, some of these text entries potentially clue at early or unused floor names.

Text	Comments
	Likely an early name for the Sheol chapter. The "7th Circle" refers to the 7th Circle of Hell in Dante's Inferno, a realm of violence.
	Likely an early name for the Caves chapter.
	Likely an early name for the Chest chapter.
	Likely another early name for Sheol. Perhaps Sheol was supposed to be more traditionally hellish?
	Hell, the sequel. Perhaps Sheol (and Cathedral) were supposed to be two floors?
	A trendy phrase at the time of this game's release. It's not clear where this might've been used.
	Unclear. Perhaps an alternate floor to Womb or Utero or an early name?
	Like "Hell2", the second floor for Meat-opolis.

Unused Room Layouts

When Wrath of the Lamb was released, a lot of room layouts were added; in fact, a handful of rooms were added that are never able to be seen in-game! These rooms exist only in the Adobe Flash assets and their ID values are never generated in-game, but Cheat Engine can be used to reveal them. They are all fully functional; they were either purposefully left out or (most likely) omitted due to an oversight during room generation.

Basement/Cellar

Unused Basement rooms: B1, B2
Unused Cellar rooms: B2

Basement Room B1
Basement Room B2
Cellar Room B2

Caves/Catacombs

Unused Caves rooms: A9, AA
Unused Catacombs rooms: AA

Caves Room A9
Caves Room AA
Catacombs Room AA

The Depths/Necropolis

Unused Depths rooms: 9A, 9B
Unused Necropolis rooms: 9B

Depths Room 9A
Depths Room 9B
Necropolis Room 9B

The Womb/Utero

Unused Womb rooms: 89
Unused Utero rooms: 89

Womb Room 89
Utero Room 89

Sheol/Cathedral

Surprisingly, there are 11 unused rooms for Sheol; however, all of these rooms save for one have an equivalent in the Cathedral that is used in-game. Some of them also appear to be similar to already existing Sheol rooms.

Unused Sheol rooms: 52, 53, 54, 55, 56, 57, 58, 59, 5A, 5B, 5C
Unused Cathedral rooms: 5C