recursal/Fanatic-Fandom huggingface dataset:
Mucormycosis

**Mucormycosis** is a passive item added in *The Binding of Isaac: Repentance*.

## Effects

* Gives Isaac a 25% chance to shoot a spore that, in addition to dealing damage, will stick to enemies.
	+ The chance is not affected by Luck.
* Spores will explode 2.5 seconds after sticking to an enemy, dealing 5 damage to and poisoning nearby enemies and firing four more spores in a cross pattern.
	+ Spores produced from Isaac's spores have homing.
	+ The spore effects will not damage Isaac.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a walking mushroom.

## Notes

* Items such as  and  will apply spores to enemies as well, despite the absence of tears.

## Synergies

* : Some fetuses stick to enemies, expand, then burst.
* : Spore explosions count as farts, and as such are increased in size.
* : Godhead's aura expands as the spore tear grows on enemies.
* : Magnetized enemies draw other enemies to them, greatly increasing the chance that spores spread to other enemies.
* : Stuck tears will block projectiles shot by attached enemies, crippling or even stopping their ability to shoot projectiles entirely.
* : The mini-spores generated by the spore explosions are affected by My Reflection.

## Interactions

* : Rerolls into the full , making  The Forgotten's unlock easier.
* //: No effect.

## Trivia

* Mucormycosis originates from the *Antibirth* mod. In *Antibirth*, this item would create a poison fart cloud on every kill, similar to . The Mucormycosis fart clouds could also knock Isaac away and potentially into hazards.
* Mucormycosis is a fungal infection caused by fungi in the order Mucorales.

## References

1. ↑ https://docs.google.com/spreadsheets/d/15K8Xgxoxdx68AIaxuLXgZoJJlG36UPgy3\_aeDpAM5tU/edit?usp=sharing
Pacer

### Found In

**Pacers** wander around the room aimlessly and can be spawned when a Gaper, a  Flaming Gaper or a Frowning Gaper is killed.

## Variations

### Stage HP

 10
 0

### Found In

**Gushers** wander around a room aimlessly, similar to Pacers, but will occasionally shoot a short ranged slow-moving, blood shot in whichever direction they happen to be moving in. They can be spawned from all the same sources as the Pacer with the addition of  Lepers which will always spawn a grey-colored Gusher upon death.

#### Notes

* Pure Magenta Champion Gushers will spit two blood shots at different intervals.

### Stage HP

 10
 2

### Found In

**Splashers** wander around a room and randomly shoot  shots.
They can be spawned when a Gurgle is killed.

### Notes

* Splashers that are spawned from Champion Gurgles appear as Champions but Splashers that spawn naturally in layouts are never seen in champion form, even if using the "CHAM P1ON" special seed.

### Stage HP

 10
 0

### Found In

Spawned after killing a Black Globin.

**Black Globin's Bodies** walk around aimlessly, occasionally spawning a Spider. They can be spawned alongside a Black Globin's Head when a Black Globin is killed.

### Stage HP

 20
 0

### Found In

Spawned after killing a Level 2 Gaper.

**Level 2 Gushers** run around a room blindly, occasionally spitting up Small Maggots.

## Gallery

* A Pacer's appearance in Downpour.
* A Pacer's appearance in Dross.
* A Gusher's appearance in Downpour.
* A Gusher's appearance in Dross.
* A Gusher spawned from a Leper.
Pyro

This article is about the item that grants bombs. For the explosion immunity item, see Pyromaniac.
**Pyro** is a passive item.

## Notes

* Rerolling this item with the , etc., will not remove 99 Bombs.
* This item can appear when using the  with 99 bombs in inventory.
* As  Tainted ??? cannot use bombs, this item has no effect. No extra poop pickups are granted.

## Trivia

* This item is used in Beans! (challenge #13).
* Pyro is a reference to pyromania, a disorder characterized by an obsession with setting things on fire. In this case it's bomb fuses.
* This item is the bomb counterpart to  and .
* This item uses a similar costume to .
Parasitoid

**Parasitoid** is a passive item added in *The Binding of Isaac: Afterbirth †*.

## Effects

* Adds a chance to fire an egg sack which spawns slowing creep. If an egg sack hits an enemy, one to two Blue Flies or Blue Spider is spawned.
* Egg sack tears have  x2 range/ x2 tear height (which also increases effective range).
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a giant humanoid fly.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a humanoid spider.

## Notes

* The chance to shoot egg sacs depends on the luck stat and is based on this formula:

m
i
n
(

1

7
−

⌊

L
u
c
k

⌋

,
50
%
)

{\displaystyle min(\frac1 { 7 - \left \lfloor \mathit{Luck} \right \rfloor}, 50\%)}

	+ At base luck (0), the chance is 14.29%, maxing out at 50% at 5 luck.
* Egg sacks will also spawn blue flies or spiders if they hit Fire Places or invincible enemies like Death's Head and Stoney.
* It is possible to create a large number of Spiders and Flies by repeatedly shooting a closed Host.

## Synergies

* : Parasitoid fetuses spawn spiders/flies and slowing creep with every hit on an enemy.
* /  / : When egg sacks are fired, they will split into smaller egg sacks. Split egg sacks from The Parasite will not look like egg sacks.
* : Egg sacks will apply their effect to every enemy hit.
* : If the explosion effect from Fire Mind triggers on an egg sack, it will produce a much larger pool of slowing creep.
* : Flies and spiders are bigger and deal double damage.

## Interactions

Overrides Parasitoid:

* Azazel

Other interactions:

* : Bomb explosions have a chance of leaving the slowing creep in a larger pool than egg sack tears, however the egg sack bombs can't spawn Blue Flies/Blue Spiders.
* : The duplicated flies will spawn on top of the enemy and deal damage immediately.
* : Tears retain Haemolacria appearance and only the main tear can spawn flies or spiders when damaging enemies.
* : Only extra range applies on egg sack tears and they will not spawn flies or spiders.
* /: No effect.
* : The sword projectiles can still spawn flies and spiders, but the swings themselves won't.
* /: Lasers are unaffected.

## Trivia

* Parasitoid is a term for when insects' larvae live inside their hosts as a parasite before eventually killing the host.
* Parasitoid is one of the only five items that count towards 2 transformations, the other four being , ,  and .
Music

The **music** in *The Binding of Isaac: Rebirth*, *Afterbirth*, *Afterbirth †*, and *Repentance* was created by Ridiculon. These soundtracks can be purchased on Steam and on Ridiculon's Bandcamp page, as well as being available on Spotify, containing 32, 9, 4, and 20 tracks, respectively. Not all tracks heard in-game are included in the OST releases, and some tracks in the OST do not appear in-game or go unused.

Most main floor tracks have a heavier variant that plays when enough enemies or bosses are in the room. In the OST, these variants are generally heard in each song’s second half. What instrument is added is listed next to each track's name in square brackets.

## The Binding of Isaac: Afterbirth †

 Delirium
 Ante Lucem (BONUS)

## Trivia

* Besides the music listed here, Ridiculon have released two unofficial albums; *The Binding of Isaac - Lullabies* (which has a colon instead of a hyphen on Spotify) and *The Binding of Isaac: Mutations.*
* Ridiculon have also released a single titled *The Binding of Christmas*, though this is only available on Bandcamp.
* Devoid and The Fallen Angel's descriptions are simply a line of underscores on Bandcamp, while they have real descriptions in the Spotify release. This was likely done to prevent spoilers, as Dark Room was new to Rebirth and not present in Flash Isaac. Terminus also has these underscores, but the description is entirely absent in the Spotify release.
* The Legend of Bum-Bo, a Binding of Isaac spinoff, has a title theme that sounds similar to and shares a name with Rebirth’s title theme.
* In an interview on Steam, Ridiculon producer Jon Evans listed the OST songs he is most proud of: “‘Sodden Hollow’ for its dripping groove. ‘Sheol’ for even being allowed to be so terrifying in a game OST. ‘Delirium’ for its dank heaviness.” He also points out that “every track we’ve written for Repentance is our fave.”
* ???’s and Home’s music both have “heavy” layers that normally cannot be heard in-game since their respective floors do not contain enemies.
	+ ???’s theme can now be heard in-game by various methods, such as using  in ???.
* The filename of Jesus Loves Viggo alludes to Viggo Bossi, Isaac’s voice actor, who sings on the track.
Pay to Play

### Collection Grid

*(page 4, column 15, row 1)**(page 4, column 15, row 1)**(page 4, column 16, row 1)*

 This article is about the item. For the challenge, see PAY TO PLAY.
**Pay to Play** is a passive item added in *The Binding of Isaac: Afterbirth*.

## Effects

* +5 coins.
* Shops, Treasure Rooms, and Libraries must be opened with a Penny instead of a Key. These doors appear identical to Arcade doors.
* All locked doors, Locked Chests, and Key Blocks must be opened with a Penny instead of Keys, including those that require 2 keys to open.

## Notes

* Locked doors, chests, and key blocks gain a unique visual where their key slot is replaced with a vertical coin slot.

## Interactions

* : Renders Mom's Locket less effective as the trinket requires a key is consumed by the lock in order to heal Isaac.
* : Thrown keys cannot unlock doors that originally were accessible by keys, but can still open chests.
* : Overridden by Pay to Play. Stores still require coins to unlock.
Razor Blade

**Razor Blade** is an unlockable activated item.

## Effects

* On use, damages Isaac for a full heart of health and grants +1.2 damage for the current room.
	+ Razor Blade takes Red Hearts before other heart types.
	+ When used more than once in the same room, damage taken is lowered to half a heart.

## Notes

* Eve starts with this item after unlocking it and donating 439 coins to the Greed Donation Machine.
	+ Both conditions must be met for Eve to hold it; donating 439 coins before defeating Satan with Eve will wrongly state on Eve's profile on the Character Selection Screen that she has it equipped.
	+ Eve starts with the Razor Blade if unlocked from the Greed Machine, even if Satan has not been defeated with Eve.
* It is possible to die using Razor Blade if Isaac does not have enough hearts.
* The effect stacks with itself and , which provides a similar benefit.
* Using this item does not affect Devil Room/Angel Room chances.
* Using the Razor Blade grants immunity frames; this allows access to Curse Rooms without losing soul hearts.
* Using this item in the Ultra Greed boss room will remove 2-4 coins and drop 1-3 pennies on the floor, as if Isaac was hit by an enemy attack.
* Using this item as  The Lost will kill The Lost, even if the protective effect from  is still active.

## Synergies

* +  as  Judas /  Dark Judas: Invokes the effect of  effect along with the original effect.
* : Spawns red wisps in the middle ring. Wisps have higher health.
* : Isaac cannot take damage from the Razor Blade, allowing for infinite uses of the item.
* / : Isaac has a chance to drop a red heart while using the item.
* : Self-damage occurs before enemy damage, making it almost impossible to lose Angel or Devil chance.
* : Isaac takes no damage while invincible, allowing for repeated free uses of the item.
* : Isaac loses half a heart instead of a full heart.
* /: Can lower Isaac's health on demand to activate the bonus.

## Interactions

* : No effect.
* /Similar effects: The shield is not broken, but Razor Blade still damages Isaac.
* Shield/Invulnerability: Will not protect against this item's damage.
* Tainted Samson/: The Razor Blade can be used in order to gain a massive damage boost in a room as long as there's a source of HP within reach.

## Trivia

* This item is used in Darkness Falls (challenge #4).
* The item itself is a reference to the act of cutting one's self, usually at the wrists, to inflict self-harm or to commit suicide by loss of blood.
* Isaac's appearance after using the item is just like the Dople.
* In the original *The Binding of Isaac*, Razor Blade was unlocked by defeating Mom's Heart/ It Lives as  Eve.

## Gallery

* The icon of Razor Blade as seen on the lower 3DS screen.
Peep Eye

**Peep Eyes** spawn in pairs and float diagonally around the room over obstacles, bouncing off of walls and other monsters and dealing contact damage to Isaac. They are completely invulnerable and can also block projectiles. They are only spawned by Peep as apart of his fight, one at 66% HP and a second at 33% HP and are destroyed once Peep is killed.

### Notes

* Cyan champion Peep Eyes spawn detached from Peep at the beginning of the fight.

## Variations

### Found In

Spawned in pairs exclusively by The Bloat.

**Bloat Eyes** spawn in pairs and behave identically to Peep Eyes but are spawned by The Bloat- both completely detached at the beginning of the fight and are destroyed once The Bloat is killed.

### Found In

**Mockuli** start off stationary, but start rapidly floating around the room diagonally when Isaac starts shooting. They stop moving when Isaac stops shooting. There is a minimum time that they move for before stopping. Unlike other Peep Eye variants they do not spawn with a correlating Monster and will be destroyed once the room they spawn in is cleared.

## Gallery

* A Peep Eye or Bloat Eye spawned by Delirium in its forms.

## Trivia

* Mockulus is a portmanteau of "mock" (to ridicule) and "oculus" (Latin for "eye").
Nicalis, Inc.

**Nicalis, Inc.** is an indie video game publisher, famous for developing and publishing *The Binding of Isaac: Rebirth* and its DLCs- *Afterbirth,* *Afterbirth+* *and Repentance*. It was founded by Tyrone Rodriguez in 2007.

## External links

* Nicalis's official website
* Nicalis's official twitter
* Nicalis's official Wikipedia page
Oob

### Found In

**Oob** will float slowly around the room randomly and occasionally spawn a Brain. If Isaac lines up horizontal to it, it charges quickly covering the room once.

## Variations

### Stage HP

 20
 6

### Found In

**Black Maws** behave like Oob but spawns Leeches instead. If Isaac lines up horizontal to it, it very quickly charges in his direction and then doubles back, charging back to its original position. It explodes upon death.

While in normal rooms Black Maws will generally charge off-screen before returning, in long horizontal rooms they can charge a random distance before returning rather than having to fly out of the room first, this can also happen if they make contact with another enemy.

Unlike the Oob, Black Maws can still summon Leeches regardless of whether they are over an obstruction or not, due to the fact that Leeches can fly.

### Notes

* They can spawn in unique Devil Room layouts if Isaac is holding the .

## Gallery

* Sketches of monsters for the Binding of Isaac: Rebirth, including what appears to be an early design of the Oob and Black Maw in the fourth rectangle of the fourth row and the fifth rectangle of the fourth row, respectively.
* An Oob on Isaac's Last Will.

## Trivia

* Oob and Black Maw are both enemies from one of Edmund McMillen's previous games named *Super Meat Boy*.
	+ Oobs have a different, but a somewhat similiar design. These extremely slowly float towards Meat Boy, but become much faster when Meat Boy is close enough to them.
	+ In *Super Meat Boy*, Black Maws work like a homing projectile that breaks into 9 smaller projectiles on impact. They appear from a black hole.
* Oobs and Black Maws are the only non-boss enemies that can charge off-screen.
	+ Black Maws specifically are also the only monsters that double back after charging off-screen, making them unique.
* Rerolling Gaping Maws with  always turns them into Oobs.
* Black Maws look surprisingly similar to the xenomorph's mouths from the *Alien* movies, but this could also be a coincidence.
	+ It also slightly resembles a sperm cell.
* Oobs have the highest health of any non-boss enemy.
* Oob's name is "boo" backwards.
Robo-Baby

**Robo-Baby** is a passive item.

## Effect

* Spawns a familiar that shoots spectral  lasers that deal 3.5 damage each.
	+ Robo-Baby shoots once per second.
	+ Robo-Baby shoots 1.36 times a second.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a three-faced version of himself.

## Notes

* Familiars that follow behind Isaac have a certain priority in how close their position is to him over other familiars, with Robo-Baby having 5th priority.

## Unlockable Achievements

* Technology Zero - Pick up any 2 technology items in a single run ( Any 2 items that have the 'tech' item tag).
Paper Clip

**Paper Clip** is a trinket.

## Effects

* Allows Isaac to unlock Locked Chests without using Keys.
	+ Locked doors, key blocks, and  Mega Chests still require keys.

## Notes

* In addition to regular trinket drop sources, Paper Clip can be obtained as a possible reward from Key Masters.
* Cain starts with this trinket after donating 68 coins to the  Greed Donation Machine.

## Interactions

* : Renders Mom's Locket less effective as the trinket requires a key to be consumed by the lock in order to heal Isaac.

## Trivia

* The pickup quote of this item is a reference to an infamous line from the first Resident Evil game.
* Paper Clip is the only Beggar payout (coming from the Key Master) that is not a passive/active item. While Rotten Beggars and Battery Bums can also pay with trinkets, they do so as random drops, rather than payout.
Odd Mushroom (Large)

This article is about the large odd mushroom. For the smaller mushroom, see Odd Mushroom (Thin). For other uses, see Odd Mushroom (Disambiguation).
**Odd Mushroom** is a passive item.

## Effects

* Gives Isaac one empty Heart container.
* Gives Isaac one full Heart container.
* +0.3 damage.
* +1 damage.
* +0.25 range.
* +1.5 range.
* +0.5 tear falling speed.
* -0.1 speed.
* -0.2 speed.
* Makes Isaac's head larger, which on its own is only a visual effect.
	+ If taken when Isaac is smaller than the default, this Mushroom also increases his hitbox slightly.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a walking mushroom.

## Notes

* There are two collectible items in the game named Odd Mushroom; you can tell them apart from the sprites.

## Interactions

* : The speed down from the Virus does not stack with the Odd Mushroom; if both are collected, only a total of -0.1 applies.
Monsters

**Monsters** refers to the many antagonistic creatures and entities the player will encounter throughout the game.

Most monsters (with few exceptions) will damage Isaac by either touching him or shooting him with projectiles. Less frequently, monsters will spawn additional, lesser monsters, spread creep, or attempt to affect the player's movement. Some monsters become tougher the further along they're encountered. Along with the more common variety of monsters, champion versions can be found lurking about; These monsters are often like their common counterparts, but have a color tint or size change, more health, and drop basic pickups on death. There are also champion versions of most bosses.

There are 196 naturally spawning monsters in total. 40 of them were added in *Afterbirth* and 21 were added in *Afterbirth †* (13 were added in Booster Packs). Almost all of these naturally spawning entities are featured in the  Bestiary.

## Monster Replacements

Some monsters have a chance to be replaced with other monsters when they spawn,  but only at room entry.  Some replacements only occur on certain floors.

(Disclaimer: Chances are approximate!)
Rib of Greed

**Rib of Greed** is an unlockable trinket added in *The Binding of Isaac: Afterbirth*.

## Effects

* Prevents Greed and Super Greed from appearing in Shop and Secret Room.
* Increases the chance of coin drops when clearing rooms at the expense of heart drops.

## Notes

* Cannot appear in Greed Mode.
* If Rib of Greed is picked up after a Greed fight in a Shop or a Secret Room, reentering the room will turn the room into a regular shop with items for sale or a secret room respectively (while keeping the previously dropped items on the floor).
	+ By dropping the Rib of Greed before entering a shop, fighting Greed, then picking up the trinket again, you can still get the shop while also having made free money from the Greed fight.
Purity

### Collection Grid

*(page 4, column 2, row 3)**(page 4, column 2, row 3)**(page 4, column 3, row 3)*

### Unlock Method

 Defeat Hush as  Magdalene

**Purity** is an unlockable passive item added in *The Binding of Isaac: Afterbirth*.

## Effects

* Grants an aura around Isaac that grants a boost depending on the aura's color.
	+ **Red**: +4 damage.
	+ **Blue**: -4 tear delay.
	+ **Blue**: +2.0 fire rate.
	+ **Yellow**: +0.5 speed.
		- Also affects maximum speed (may never exceed 2.0).
	+ **Orange**: +7.5 range, +1.0 tear falling speed.
	+ **Orange**: +3.0 range.
* Taking damage causes the aura to disappear. When the next room is entered, the aura will reappear with a random color.

## Notes

* The tear delay boost can allow the player's tears to go over the normal maximum rate of fire.
* It is especially difficult for  The Lost to change auras. However, it is possible through the use of .
* As  Tainted Isaac you can easily change auras by swapping Purity for another item and picking it back up again.
* Picking up multiple copies will still grant a single aura, not providing any advantage.

## Trivia

* There is a card in Slay The Spire with similar name and appearance.
One Tooth

### Found In

**One Tooths** slowly fly towards Isaac, charging at random intervals at considerably higher speed. They will shy away from Isaac if directly approached.

## Notes

* Two One Tooths will spawn in the secret crawlspace created by killing  Great Gideon using a .

## Variations

### Stage HP

 50 35
 0

### Found In

**Fat Bats** move slower than a One Tooth but have more health. Fat Bats try to align themselves diagonally to Isaac, giving them a tendency to avoid his shots. They will try to shoot at Isaac once they are diagonally aligned.

## Trivia

* Fat Bats were first revealed for the Afterbirth DLC in a Binding of Isaac official website post.
Number Magnet

**Number Magnet** is an unlockable trinket added in *The Binding of Isaac: Repentance*.

## Effects

* Increases Devil Room chance by 10%.
* Prevents Krampus from appearing in the Devil Deal.
* If held before visiting the Devil Deal, the room's layout will be replaced with one of 11 special Devil Room layouts (6 in Greed Mode). These rooms contain 0-3 Devil Room items (most commonly 2-3), 1-3 Black Hearts, and several enemies from Sheol.

## Trivia

* This trinket resembles one of the the three sixes from .
Nerve Ending

**Nerve Endings** are purely static enemies with no proactive means of dealing damage. They can deal contact damage, but only if Isaac somehow walks directly into them.

## Variations

### Stage HP

 20
 0

### Unlock Method

 Defeat The Lamb

**Nerve Ending 2s** are stationary enemies which will swipe at Isaac if he gets too close. This attack can only connect if Isaac is horizontal with it, but will deal contact damage in any case if Isaac walks into them. Otherwise, they have no means of attacking and are generally harmless.

#### Notes

* Nerve Ending 2 can never replace regular Nerve Endings next to doors.
* If Nerve Ending 2s aren't unlocked yet, they are replaced by Nerve Endings.

## Trivia

* It's possible that the Nerve Ending is a giant axon, an electrical impulse terminal for nerve cells, which could explain its name.
Mother's Kiss

**Mother's Kiss** is an unlockable trinket added in *The Binding of Isaac: Repentance*.

## Effects

* Grants one heart container while held.
	+ This heart container will be filled the first time the trinket is picked up.

## Notes

* If the only heart container Isaac has is the one given by Mother's Kiss, the trinket will be destroyed if the heart container is traded/consumed.
	+ The trinket will get destroyed even if smelted via , , or a Gulp! pill.
* If Isaac drops the trinket while he only has one heart container for health, he will have no health and die instantly.
	+ This also means that using  card will do the same, even if he has soul hearts.
* The extra red heart container can exceed the maximum coin heart container limit of  Keeper and  Tainted Keeper, allowing them to obtain more than 3 or 2 coin hearts, respectively.
* The heart added is a soul heart for  ??? and  Tainted Bethany, and a black heart for  Dark Judas and  Tainted Judas.
	+ Using The Fool? card as one of these characters while holding this item will kill you instantly, as it drops the trinket, removing the last half soul heart that you normally would remain with.
* The Forgotten will always get a Bone Heart regardless of whether the body or the soul picked up the trinket.

## Synergies

* ??? /  Dark Judas /  Tainted ??? /  Tainted Bethany /  Tainted Judas /  Tainted Forgotten: If Mother's Kiss is picked up while having 12 Soul/Black Hearts, Mother's Kiss will not trigger until damage is taken. However, if only half a heart of damage is taken, Mother's Kiss will immediately restore the health back to a full 12 but believe its effect failed due to not restoring a full heart's worth, allowing it to trigger again and again until a full heart of damage is taken, after which it will cease taking effect. If combined with , this makes any of the aforementioned 6 characters virtually invincible as long as their health is not reduced in any way through Devil Deals, Health Down pills, etc.
* Golden Trinket / : Adds 2 heart containers.
	+ If the trinket is picked up while holding **Mom's Box**, only 1 heart container will be filled.
* : The trinket will be consumed, but the soul hearts from conversion are kept.
* : The trinket will be consumed, but the damage and  is kept.

## References

1. ↑ https://www.youtube.com/watch?v=J\_L8jJee0dM
Poker Chip

**Poker Chip** is an unlockable trinket added in *The Binding of Isaac: Afterbirth*.

## Effects

* If a Chest would contain Hearts, Coins, Bombs and/or Keys, it has a 50/50 chance to either drop extra consumables or replace all of its contents with an Attack Fly.
* The trinket has no effect on Red Chests, or if the chest would contain a pill, a card, a trinket or an item.
	+ Consequently, the Chip has no effect in Chest or Dark Room.

## Notes

* Has no effect on Old Chests.
* When opening a Mega Chest yields pickups, it can spawn 1-2 Attack Flies alongside the pickups.

## Synergies

* : Provided the Poker Chip is not smelted, it can be used in conjunction with the eye to open all chests with extra pickups, while dropping the chip for any chests containing flies, nullifying the downside of the trinket.
* : Enemies killed by keys have a 50/50 chance to spawn extra pickups or an Attack Fly: The attack fly will be instantly killed by the thrown key.
Necropolis

*(chapter 3)*

### Unlock Method

 Beat all Depths bosses ( except Reap Creep) (not restricted to beating bosses *in* The Depths)

**Necropolis** is the alternative chapter of the Depths. It is a dark environment infested with insects.
Unlike The Depths, Necropolis must be unlocked for it to appear.

Necropolis is unlocked by defeating every boss from The Depths at least once.

The boss of Necropolis II is always Mom.

## Bosses

### Final Boss

Mom will always appear on the second floor of this chapter or in the last boss room if Curse of the Labyrinth is active.

## Unlockable Achievements

* Something Sticky - Beat Chapter 3 20 times.

* Leprosy - Beat Chapter 3 without taking damage.

* Dark Boy - Beat Chapter 3 without taking damage.

## Trivia

* A necropolis is a large ancient cemetery with elaborate tomb monuments. In Ancient Greek, νεκρόπολις or *nekropolis* literally means "city of the dead".
* In the original *The Binding of Isaac*, Daddy Long Legs, Triachnid, Carrion Queen, and The Wretched could appear as bosses.

## Music

* The music for Necropolis is titled *When Blood Dries*.
Polycephalus

Double Trouble

Degraded Boss

**Polycephalus** is a boss that can appear:

* In the Catacombs and the Flooded Caves.
* Only in the Catacombs.

## Behavior

Polycephalus burrows underground when Isaac is not within range. While burrowed he becomes invincible and follows Isaac's movements. When close to Isaac, he pops out and performs one of the following attacks:

* Sprays out a cluster of projectiles towards Isaac, similar to Monstro, but more drawn out.
* Fires a spread of 3 projectiles at Isaac.
* Shoots out 8 projectiles in all directions.
* Summons a Round Worm.

He will stay vulnerable for a few moments after performing an attack before quickly burrowing underground again.

## Champion Versions

 **Red**: Summons Para-Bites instead of Round Worms. All projectile attacks are replaced with a ring of six projectiles.
 **Pink**: Two Polycephaluses, each with 50% HP (100), replace the normal Polycephalus. They do not spawn Round Worms.
## Gallery

* Polycephalus in-game.
* Red Champion Polycephalus.
* Pink Champion Polycephalus.
* Polycephalus as one of  Delirium's forms.

## Trivia

* The Stain is his posthumous version, who also shows up in Chapter 2. Polycephalus is one of four bosses to have their posthumous version in the same chapter, the others being Gemini having Blighted Ovum in Chapter 1, Chub having Carrion Queen in Chapter 2 and the  Tuff Twins having  The Shell in Chapter 2.5.
	+ However, Polycephalus is the only one of them to have their posthumous version in the same environments as well, sharing both the Catacombs and the Flooded Caves with The Stain. The only difference is that The Stain can appear in Caves as well, where Polycephalus cannot.
		- This is no longer the case as of Repentance, since Polycephalus no longer appears in the Flooded Caves while The Stain no longer appears in The Catacombs.
* Polycephaly is the condition of having more than one head.
* Polycephalus shares his name with a cactus.
* Polycephalus is one of the four bosses that can be spawned by It Lives, the other three being Chub,  Fistula and Teratoma.
* Prior to Booster Pack #5, Red Champion Polycephalus could spawn Scarred Para-Bites if he was fought in the Scarred Womb.
Needle

### Found In

**Needles** are monsters that resemble a miniature Pin, and added in *The Binding of Isaac: Repentance* DLC.

They lunge towards Isaac in an attempt to deal contact damage. Before they lunge, they are characterized by a small lump in the ground. Unlike Pin, they do not move underground relative to where they land. Instead, they teleport to a spot near Isaac before lunging. They can leap over pits and obstacles to reach Isaac if he has flight.

Needles will not leave a cloud of smoke upon spawning within a given room.

## Variations

### Stage HP

 10
 2

### Found In

 (Ashpit only)

**Pasties** are skeletal variants and behave exactly like the Needles. However, when emerging off the ground, they will shoot 4 blood shots on the ordinal directions. The appearance of Pasty is similar to The Frail's in its second phase.
Mr. Fred

**Mr. Fred** is a boss that can appear:

* In the Womb and the Utero.
* In the Womb and the Scarred Womb.

## Behavior

Mr. Fred stays stationary in the middle of a 1x2 or 2x1 room and performs the following attacks:

* Breaks the chain of 1 of the 4 Homunculi that accompany him at the beginning of the fight.
	+ Unlike other Homounculi, the ones spawned with Mr. Fred can not break free on their own and can only be unleashed by this attack.
* Shoots 4 large long-range blood projectiles in the cardinal directions. These tears leave Red Creep and will burst at the end of their range into a larger pool of Creep.
* Burrows underground briefly and pops back up in his original position, firing eight projectiles in all directions.
* Spawns a Fred on his position, which immediately burrows underground.

Mr. Fred deals a whole heart of contact damage.

## Gallery

* Mr. Fred in-game.
* Mr. Fred releasing a Homunculus.
* Mr. Fred as one of  Delirium's forms.

## Trivia

* Mr. Fred is the boss version of the Freds.
* Mr. Fred resembles a large baby with a medical condition Harlequin Ichthyosis. He could, therefore, be a giant Harlequin Baby.
* Unlike other bosses, Mr. Fred disappears upon death instead of exploding into blood.
* Similar to Delirium's room, if Mr. Fred spawns in The Void, his room will be seen in the map as a 1x1 room.
* Mr. Fred's boss art shows the ground around him to be grey, instead of a fleshy red.
Robo-Baby 2.0

### Collection Grid

*(page 3, column 2, row 7)**(page 3, column 2, row 2)**(page 3, column 3, row 2)*

### Unlock Method

 Complete Computer Savvy (challenge #16)

**Robo-Baby 2.0** is an unlockable passive item.

## Effect

* Spawns a familiar that automatically shoots  lasers towards enemies when aligned with them, dealing 3.5 damage per shot.
	+ The familiar will move in the direction Isaac is shooting.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a three-faced version of himself.

## Notes

* Unlike , Robo-Baby 2.0 cannot be controlled with the mouse if mouse control is enabled in the config files.

## Unlockable Achievements

* Technology Zero - Pick up any 2 technology items in a single run ( Any 2 items that have the 'tech' item tag).
Purist

**Purist** is challenge #20. This challenge is unique because Isaac starts with no items. The goal is to defeat Mom's Heart or It Lives. This Challenge is unlocked after defeating Mom for the first time.

## Difficulty

Because there are no Treasure Rooms, it is harder to find items. While this is standard for most challenges, Isaac also doesn't start with any items.

## Strategy

* Other special rooms become much more important, with Devil Rooms and Angel Rooms becoming even more valuable than on an average run.
* Cards such as  and items such as ,  and  can be used for the Shop and Devil Room items, with Diplopia cloning the items, and Credit Card/Coupon allowing the item(s) to be taken for free. Neither option stops Angel Rooms from appearing.
* Bombs are much more valuable when hunting for Secret Rooms as these can provide free items.
* Curse Rooms guarantee damage and can lower the chances of Devil Rooms. However, if Isaac has a full Soul Heart, Black Heart, or  Bone Heart, the reward can outweigh the damage and still allow Isaac to access a Devil Room. Alternatively, wait to enter the Curse Room until after visiting the Devil Room.
* can be used to instantly win the boss fights against Mom, which can be used to preserve key health, and Mom's Heart/ It Lives, which will complete the challenge.

## Reward

* Rune of Berkano - Complete **Purist (challenge #20)**.
Plum Flute

**Plum Flute** is an unlockable activated item added in *The Binding of Isaac: Repentance*.

## Effects

* On use, summons Baby Plum to fight for Isaac in the current room for ~10 seconds.
	+ Baby Plum will always twirl, jump, then spit blood and bounce around the room before waving goodbye and flying away.
	+ Baby Plum does 12 contact damage per tick (24 per second), 3.5 damage per shot, and 2 damage per tick with creep (20 per second).
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a giant humanoid fly.

## Notes

* If Isaac goes enough time (about half a minute) without hurting Baby Plum during a boss fight, she will fly away and leave behind a Plum Flute on the Boss Room pedestal.
	+ Damage done with  does not count as hurting Baby Plum.
	+ Damage done indirectly, like losing Black Hearts, does not count as hurting Baby Plum.
	+ Damage dealt passively by familiars such as , , and  does count as hurting Baby Plum.

## Synergies

* : Baby Plum's shots that pass through the Prism will be split into four.
* : Spawns a wisp on the middle ring, resembling Baby Plum. When the Baby Plum spawned from using Plum Flute bounces diagonally around the room, all the wisps will bounce around the room and fire tears behind themselves as well. The wisps are invulnerable while bouncing around the room.
* : Summons two Baby Plums, the Baby Plums start out overlapped but can sometimes split up when using different attacks.
* : Affects Baby Plum's blood puddle.
* : Baby Plum can be sacrificed for free, instead of a familiar. Plum Flute can still be used as normal afterwards.

## Interactions

* : No effect.
* / : Doubles Baby Plum's contact damage, but not projectile damage. Plum is also larger.
* : Plum Flute will still function normally if the boss Baby Plum is erased.

## Trivia

* Plum Flute resembles the Poké Flute, an item that appears in various Pokémon games and is used to wake sleeping Pokémon.

## Bugs

If she was doing her spit attack, her and her projectiles will end up stuck in place and she will not stop attacking until the player leaves the room.
NO!

This article is about **NO!**, similar in appearance to Nuh Uh!.
**NO!** is a trinket added in *The Binding of Isaac: Afterbirth*.

## Effect

* Prevents activated collectibles from being generated, if possible, from all item pools while this trinket is being held.

## Notes

* Activated items will start appearing again once the item pool's non-activated items are exhausted or become scarce.
* When the trinket is dropped, the item generation mechanics go back to normal, and active items will be generated normally again.
* In runs where many items have been collected/rerolled, the trinket can function as a sort of warning to the player that an item pool will soon be exhausted if activated items begin to show up.
* Fixed boss drops and machines are not affected by **NO!**:
	+ from Pride.
	+ from Sloth.
	+ from a Fortune Telling Machine.
	+ from Krampus.
	+ from a Blood Donation Machine.
	+ from Wrath.
	+ from The Headless Horseman.
	+ from Envy.
	+ from Conquest.
	+ from Super Lust.
* Most fixed active item drops are prevented:
	+ Pride drops a Key.
	+ Sloth drops a card.
	+ Krampus always drops .
	+ Blood donation machines drop a  if unlocked, still  otherwise.
	+ Wrath drops Bombs.
	+ The Headless Horseman and Conquest drop either  or .
	+ Envy drops a Troll Bomb.
	+ Super Lust drops a pill.
* Some active items that are hard-coded to appear in certain rooms will still spawn, such as Grave Rooms that contain  or Dross rooms that contain .

## Synergies

* Golden Trinket / : Items with 0 quality are rerolled.

## Interactions

* : Will not be prevented from spawning, since it's treated as a passive item. Is nigh-guaranteed to spawn in a Library.
* : Death Certificate's item generation ignores NO!'s changes to item availability.
* : Additional copies of Magic Skin can still replace other items.
* : Active items generated by TMTRAINER will not be prevented from spawning.

## Gallery

* NO!'s original appearance before Booster Pack #5.
Obstacles

**Obstacles** are objects that are meant to get in Isaac's way in rooms. Obstacles have a variety of effects, either doing nothing, acting as a gate, dealing damage to Isaac, exploding, providing loot, or slowing him down. These obstacles can be found scattered throughout rooms, with some occuring on more floors than others.
Mystery Gift

**Mystery Gift** is an unlockable activated item added in *The Binding of Isaac: Afterbirth † (Booster Pack #1)*.

## Effects

* Upon use, spawns a random item from the current room's item pool, with a base ~17% chance to spawn  or  instead.

## Notes

* The chance to get  or  is determined by Luck using this formula:

2

12

⌊

L
u
c
k

⌋

{\displaystyle \frac2 { 12 + \left \lfloor \mathit{Luck} \right \rfloor}}

	+ A table showing an example is below. There's no cap, with diminishing returns. At 88 Luck the chance drops to 2%.

 8 | 90% | 10%

* A Lump of Coal and The Poop are fixed drops, and cannot be changed by having , holding , and other similar effects.
* Spawning The Poop will create a poison cloud, as if having used , down to matching the former item's effects.

## Synergies

* : Spawns a random wisp. For the rest of the run, a random wisp spawns after clearing a room if the one given by the item was destroyed, including the replacement wisps given by this effect.
* : When Damocles is activated, a second item will be spawned with adherence to the item pool for the current room. Even if Mystery Gift "fails" and spawns either  or , a second item from the current room's item pool will always be rewarded.

## Interactions

* : No effect, Mystery Gift will only spawn a single item.
* : Like all single-use active items, this item cannot be absorbed by Void. Instead, it will consume and use the Mystery Gift.
	+ Mystery Gift will be absorbed and will spawn the item upon Void's next use.

## Trivia

* Mystery Gift is based on this Steam Workshop item by Striped.
* The appearance and pickup quote of the item is a reference to the game Spelunky.
* The item's name is also a reference to the *Pokémon* franchise's feature for distributing event Pokémon.
* The item having a chance to give A Lump of Coal references Santa's tendency to gift coal to naughty children.
* The item having a chance to give The Poop references one of Isaac's floor transition's dreams, in which he is gifted poop.

## Gallery

* Mystery Gift's appearance prior to Booster Pack #2.
RC Remote

**RC Remote** is an unlockable trinket added in *The Binding of Isaac: Repentance*.

## Effects

* Instead of trailing behind Isaac, familiars are directly controlled by the same inputs as Isaac's.
* Holding the drop button will allow Isaac to move while keeping the familiars in place, identical to  Jacob and Esau.

## Notes

* This trinket affects the same familiars  effects. For a list of the familiars unaffected by this trinket, visit King Baby's page.
* Throwable familiars do not return to Isaac upon impact; instead, they treat their impact location as their new "launch" location, and can be fired in any direction from there. The only exception is  which will return to the location it was launched from.

## Synergies

* + : Familiars affected by Friendship Necklace are still considered orbitals regardless of positioning allowing Isaac to use their contact damage without getting close to enemies. RC Remote also prevents familiars that weren't already orbitals from flashing when Spin to Win is used despite still being affected by the active item.
* : Familiars are not held in place while firing but still auto-target enemies.
* Lilith:  can be positioned on top of Lilith, effectively removing Lilith's downside.
* Tainted Forgotten: Familiars will move with Tainted Soul, and not follow behind Tainted Forgotten like they normally do. This is massively beneficial as it allows Tainted Soul to have actual protection against enemies. Orbitals still remain orbiting Tainted Forgotten as expected.
Montezuma's Revenge

**Montezuma's Revenge** is an unlockable passive item added in *The Binding of Isaac: Repentance*.

## Effects

* Continuously shooting for 2.35 seconds allows Isaac to fire a short-ranged brown  laser and corn shots behind himself by releasing the fire button.
	+ The laser deals Isaac's damage per tick (15x Isaac's damage per second), ticks up to 19 times and lasts ~1.28 seconds (77 frames).
	+ Corn shots deal 6 damage, and a random amount are created each blast.
* This item belongs to the  set. Collecting three items from this set will transform Isaac into a walking pile of poop.

## Synergies

* Montezuma's Revenge, ,  and  all have the same charge time, allowing Isaac to easily utilize them at same time.
* : Can cause the poop beam to hook to a target anywhere in the room, potentially hitting a target far outside of its usual range.
* : The corn Isaac poops out can be sliced, giving Isaac an insane damage up in seconds.
* : Enemies hit by the sneeze will gain a curse that increases the damage the poop beam deals to 2x and +3 flat damage. Enemies who die to the poop beam under the curse will damage and spread the curse to nearby enemies.
* : The poop beam will unleash a barrage of explosions at the end of it.
* : The brown laser Isaac fires will produce random arcs of electricity at the end of the laser. The corn Isaac poops out does not interact with the electricity.
* : Spawns a large amount of tears at the end of the poop beam, heavily increasing Isaac's damage output.
* : Causes the poop beam range behind Isaac to become significantly increased as well as having a short range similar to Azazel's beam in front of him. This greatly eases the use of this item allowing for high DPS.
* : The poop beam splits into two horizontal beams meaning less risk for Isaac and a bigger area for enemies to be hit.

## Interactions

* : No effect.
	+ **Eye of the Occult** + /: The poop beam also automatically fires at the crosshair and becomes a lasso. The loop starts where the beam would normally end and extends out to the cross-hair.

## Trivia

* Montezuma's Revenge is a colloquial term for Traveler's Diarrhea, an intestinal infection caused by ingesting contaminated food or water. Montezuma II was the last Aztec ruler before the Spanish conquest of the Aztec civilization, and the sickness is seen as a curse afflicting tourists visiting Mexico as revenge for the Aztec massacre.
Orphan Socks

**Orphan Socks** is a passive item added in *The Binding of Isaac: Repentance*.

## Effects

* Gives Isaac +0.3 speed and 2 Soul Hearts.
* Isaac becomes immune to spikes and creep.

## Notes

* Does not prevent damage from Curse Room doors, Spiked Chests, or spiked rocks but does protect against spiked rock bridges.
* Does not prevent use of a Sacrifice Room.

## Interactions

* : Does not offer immunity against spikes placed around pickups.

## Trivia

* Orphan Socks is from the *Antibirth* mod. In *Antibirth*, it would allow Isaac to only take damage from Curse Room doors via exiting them similar to flight and give  Magdalene immunity all together in Cursed! (challenge #10).
	+ Prior to *Antibirth* the item originated from the *Binding of Isaac: Community Remix* mod for the original Binding of Isaac flash game, where it was called "The Socks."
* The "your feet feel stronger" part of the description is exactly the same as the description of , which gives Isaac the immunity to spikes and creep.
* Orphan Socks is the rarest item that can be acquired from a Locked Chest, along with .
Pride

Degraded Mini-Boss

**Pride** is a mini-boss based on one of the Seven Deadly Sins.

## Behavior

Pride wanders randomly around the room and performs one of two attacks:

* Spawns 4 Troll Bombs in random sections of the room.
	+ Pride is immune to damage from his own Troll Bombs.
* Fires 4 wave-like lasers from himself in an X-pattern.

Pride deals a whole heart of contact damage.

## Unlockable Achievements

* The Book of Sin - Defeat all 7 Deadly Sins.

## Trivia

* Pride's grayscale color, simple design, and the wavy scribble-like appearance of his lasers make him resemble Isaac's drawings as seen in the game's menus and cutscenes, possibly meaning he represents the pride Isaac takes in his creations.
* Pride's expressions during its attacks are a reference to "rage comic" memes, he briefly resembles troll face before spawning Troll Bombs and assumes a forever alone before firing lasers.
* The Seven Deadly Sins that these mini-bosses are based upon are, in Christian teachings, a classification of vices from which all others are derived.
* Pride is the personification of one of the Seven Deadly Sins. Pride is the excessive belief in one’s own importance, and can be thought of as narcissism, entitlement, or egotism. Pride can lead to other sins such as excessive desires for fame/attention, selfish desires for power, disobedience, discord, hypocrisy, and vanity. Pride is also believed by many to be the root of all sins.
Petrified Poop

**Petrified Poop** is a trinket that has a 1/200 (0.5%) chance to drop from Poop.

## Effects

* Increases pickup drop rate from poops to 50%.

## Notes

* Can be used when fighting bosses that spawn poop like Larry Jr. or Dingle, although the drop rate is greatly decreased in these rooms.
* Not affected by Luck.

## Synergies

* /: Grants poops made from enemies a chance to drop pickups.
* Golden Trinket / /: Each effect/trinket copy further increases the chance for poops to drop pickups.
* Very effective with .

## Interactions

* /: Poops made from enemies do not drop pickups.
* / Tainted ???: No effect on thrown poops.

## Trivia

* This trinket is used in Challenge #2 (High Brow).
* This trinket seems to be in reference to Coprolites, very old pieces of poop that have become fossilized over a very long time.