The Binding of Isaac Wiki
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Steam art by Edmund McMillen.

The Binding of Isaac is an indie game created by Edmund McMillen and Florian Himsl, with music composed by Danny Baranowsky. It was released on the digital distribution platform Steam on September 28, 2011. The player controls a nude crying child named Isaac or one of six other unlockable characters. After his mother is given a message from God commanding her son be sacrificed as proof of her faith, Isaac flees into the horror-ridden basement to stay alive.

The game can be only downloaded on Steam for $4.99 USD, with support of Microsoft Windows, Mac OS X, and Linux. On November 1, 2011, the game was included in the Humble Indie Bundle as part of the Humble Voxatron Debut.


The Binding of Isaac is a two-dimensional Action-adventure game where the player controls Isaac or six of the unlockable characters as he traverses through the dungeons located underneath his mother's basement. The video game's gameplay and style are inspired by the dungeons of The Legend of Zelda series, while mixing in randomly procedurally generated floors akin to Roguelikes (like traditional roguelikes, death is permanent and the player is forced to restart with nothing if they die) while doing this is in a simple Legend of Zelda like formula. On each floor of the basement below, the player must fight off monsters before he can go into other rooms. Along the way, the player can collect currency to buy items from shops, keys to gain entry into special treasure rooms (as well as special golden chests, libraries that contain book items, and shops), and new weapons and power-ups to increase his chance of surviving. Each floor of the dungeon ends in a boss room, where the player must defeat the boss before being able to go down to the next floor.


The Binding of Isaac's storyline is based off the eponymous Bible story. Isaac (a kid) and his mother live in a small home situated on a hill, both peacefully keeping to themselves, with Isaac drawing doodles and playing with his toys while his mother watches Christian broadcasts on the television. Isaac's mother then hears "a voice from above", stating her son is corrupted with sin and must be saved. It asks her to remove all sin from Isaac to save him. She obliges, taking away his toys, pictures, his handheld video game console and even the clothes on his back.

The voice again calls out to Isaac's mother, stating Isaac must be isolated from all the evil in the world. Once again, she follows its command and locks Isaac in his room. Finally, the voice speaks to her again. It states she has done well but says it still questions her faith and commands she must sacrifice Isaac. She obliges, grabbing a kitchen knife and goes to Isaac's room. Isaac is watching through a sizable crack in his door and starts to panic. He finds a trapdoor under the rug, and just as his mother bursts in, he opens the trapdoor and jumps down it. Isaac then puts the paper he was drawing onto his wall, which transitions into the game's title screen.

Shown throughout the game at loading points between floors is Isaac recollecting about his childhood while curled up in a fetal position and crying. These purportedly show parts of his life, showing Isaac had a difficult childhood ranging from rejection from his mother to bullying from his classmates. However, some images show impossible scenes that cannot have happened but are rather Isaac's own fears. Along with that, the game resumes with Isaac waking up on the next floor making it possible that the memories are merely made up dreams.

The game has multiple ending scenes, making the storyline distorted and non-linear as the game continues.


This is a list of all vanilla content and features up to date.


Main article: Characters
Character Hearts Speed Shot Speed Damage Tear Rate Starting item(s)
Isaac 3 2 2 2 2 The D6 (When unlocked)
Magdalene 4 2 2 2 2 Yum Heart
Cain 2 3 2 3 1 Lucky Foot
Judas 1 2 2 4 2 Book of Belial
Eve 2 3 2 1 2 Whore of Babylon & Dead Bird
??? -1 2 2 2 2 The Poop, 3 Soul Hearts
Samson 1 2 2 2 2 Bloody Lust, 1 Soul Heart


Main article: Bosses
Boss Health Found In
The Duke of Flies 110 Chapter 1 (The Basement, Cellar)
Gemini TBA The Basement
Monstro TBA The Basement
Larry Jr. 22 (per segment) The Basement
Famine TBA Chapter 1
Steven 280 The Basement
Widow 130 Cellar
Pin 157.5 Cellar
The Blighted Ovum 140 Cellar, The Catacombs
Gurdy Jr. 250 Cellar, The Catacombs
Fistula 60 (Large)

15 (Medium) 8 (Small)

The Caves
Gurdy 595 The Caves
Peep TBA Chapter 2 (The Caves, The Catacombs)
Chub 350 The Caves
Pestilence 280 Chapter 2
C.H.A.D. 350 The Caves
The Carrion Queen 175 The Catacombs, Necropolis
The Husk 143 The Catacombs
The Hollow 22 (body)

53.6 (head)

The Catacombs
The Wretched 215 The Catacombs, Necropolis
Monstro II 632.5 The Depths
Loki 350 Chapter 3 (The Depths, Necropolis)
War 500 Chapter 3
Gish 632.5 The Depths
Mom TBA Chapter 3, Final Boss
Mask of Infamy 200 (Heart)

150 (Mask)

Daddy Long Legs 300 Necropolis, Chapter 4 (The Womb, Utero)
The Bloat 450 Necropolis, Chapter 4
Scolex 300 The Womb
Blastocyst 190 (Big)

75 (Medium) 30 (Small)

The Womb
Triachnid 300 Chapter 4
Death 450 Chapter 4
Conquest 500 Chapter 4
Mom's Heart 950 Chapter 4, Final Boss
It Lives 950 Chapter 4, Final Boss
Lokii 350 (each) Chapter 4
Teratoma 60 (Large)

15 (Medium) 8 (Small)

Satan TBA Sheol
Isaac (boss) 2000 Cathedral
??? (boss) 2000 Chapter 6 (The Chest)
The Fallen 60 The Basement, Chapters 2, 3 & 4, Sheol
Headless Horseman 60 (Body)

100 (Head)

Chapters 1, 2, 3 & 4
Krampus TBA Any Floor (in the Devil Room)


Main article: Monsters

Coming soon.


Main article: Items

Coming soon.


Main article: Chapters

Coming soon.


Main article: Rooms

Coming soon.


Coming soon.


Wrath of the Lamb[]

Main article: The Binding of Isaac: Wrath of the Lamb

A DLC expansion was added to the game, titled Wrath of the Lamb, was released through the digital distribution platform Steam on May 28, 2012. The expansion adds 70% more content to the vanilla version, and contains +25 new bosses, +100 new items, +30 unlockable content, a new final ending and more.

Eternal Edition[]

Main article: The Binding of Isaac: Eternal Edition

A DLC expansion was added to Steam on May 2, 2015 titled Wrath of the Lamb: Eternal Edition, for free for all owners of the Wrath of the Lamb expansion. The expansion adds a new Hard Mode difficulty which contained Eternal Variants of bosses and monsters, as well as bug fixes and optimizations.


The Binding of Isaac received mostly favorable reviews from game critics and gamers alike. On the review aggregator GameRankings, the game has an average score of 85.17%, based on 18 reviews. On Metacritic, the game has an average of 84/100 based on 30 reviews.

In Germany, the game has received an age 16+ rating because of the potentially blasphemous content.


Due to its global success, the game spawned a small series.

The game received a complete remake titled The Binding of Isaac: Rebirth and was released on November 4, 2014. The following DLCs for Rebirth were released: Afterbirth was released on October 30, 2015, Afterbirth † on January 3, 2017, and Repentance on March 31, 2021.

A card game based on the series, titled The Binding of Isaac: Four Souls, was released on November 2018. Its expansion, titled Requiem, was announced.

A prequel spin-off, The Legend of Bum-bo, was released on March 2020.


  • In Blade Strangers, Isaac appeared as one of the playable characters.
  • In Crystal Crisis, Isaac appeared as one of the playable characters.
  • In Team Fortress 2, the ram horns featured from picking up the Brimstone item were added as an item to promote The Binding of Isaac: Rebirth.
  • In Mew-Genics, another game by Edmund McMillen, one of the cats has a face referencing Isaac.


  • Before the game's official title was finalized, it was first originally named Love Sick and then Mom.[1]
  • The game's name and storyline reference the Biblical story known as the Binding of Isaac.
  • Edmund had tweeted that the game would receive a port on the Nintendo 3DS via the Nintendo eShop and was waiting for approval from Nintendo. Nintendo later rejected it, not based on the violence and dark setting, but rather the "questionable religious content".
    • The decision brought him to praise the Steam platform and the free reign it gave publishers regardless of the game's content (compared to Nintendo). Nintendo's rejection caused a public outcry among major gaming websites.
    • Relative to the remake of the game, Edmund has reached out to Nintendo to get the game released on the Nintendo 3DS. He stated the remake has a better chance with Nintendo now, due to the new 16-bit style as well as that the game had became a surprise hit. Some time later however, Edmund stated on his Formspring that there is virtually no chance for Rebirth to come out on the 3DS at this point, due to the religious content restrictions.
    • However, despite these previous events- Rebirth actually has been released for the New 3DS on the eShop, presumably due to Nicalis being an established and quite successful Nintendo eShop developer and publisher.



Games and DLCs The Binding of IsaacWrath of the LambEternal EditionDemo
Other Purchases Unholy EditionOriginal SoundtrackArtbookSteam Trading CardsMerchandise
Miscellaneous Cut Content