Binding of Isaac: Rebirth Wiki

Gapers walk towards Isaac by the most direct route possible. They will actively path around obstacles and other enemies that block their path to Isaac. Upon death, they will usually transform into a Pacer Pacer or Gusher Gusher.


Frowning Gaper[]

Frowning Gapers walk slowly toward Isaac (though faster than Gapers) and deal contact damage. They start out with their eyes closed, and when they have line of sight with Isaac, they will open their eyes and gain extra permanent speed. Upon death, they will usually transform into a Pacer Pacer or Gusher Gusher.

Flaming Gaper[]

Added in Afterbirth

Flaming Gapers walk slowly toward Isaac (slightly faster than Gapers) and deal contact damage. Upon death, they will usually transform into a Pacer Pacer or Gusher Gusher.


  • Unlike other flaming enemies, they are not immune to damage from fire sources and regular Gapers will not turn into Flaming Gapers upon contact with any source of fire.


Nulls walk slowly toward Isaac (similarly to Frowning Gapers) and deal contact damage. They start out with their eyes closed, and when they have line of sight with Isaac, they will open their eyes, though without a speed increase. They periodically fade into and out of visibility.


  • White Champion Nulls may not be able to turn invisible while invincible.
  • They are referred to as "Nulls", which goes both for its singular and plural usage.
  • Added in Afterbirth The health bar that Spider Mod Spider Mod adds to enemies will not appear under a Nulls while it is invisible.


Added in Afterbirth

Cyclopias moves toward Isaac (slightly slower than Gapers), dealing contact damage and leaving behind a short-lasting trail of damaging Red Creep. Occasionally shoots a blood shot towards Isaac.


Gurgles walk towards Isaac (significantly faster than Gapers), dealing contact damage and periodically firing Ipecac Ipecac shots at him. These shots can kill other enemies caught in their blast radius, but Gurgles themselves are immune to their own shots as well as Ipecac shots, bombs, and Added in Repentance fireballs from other monsters. They can turn into a Splasher Splasher upon death.


Added in Repentance

Crackles walk towards Isaac at the same speed as a Gurgle, dealing contact damage and periodically shooting a fireball which releases 4 lines of fire in the cardinal directions when it touches the ground. These lines of fire span the length and height of a normal sized room. Like the Gurgle, they are immune to fireballs, Ipecac shots, and bombs from other monsters.

Blue Gaper[]

Added in Afterbirth

Blue Gapers walk towards Isaac slightly faster than Gapers, and deal contact damage. They are mainly spawned by Hush Hush.


Greed Gaper[]

Added in Afterbirth

Greed Gapers walk toward Isaac, dealing contact damage. They are mainly spawned during the Ultra Greed Ultra Greed boss fight.

Added in Repentance If they deal contact damage to Isaac,they will force Isaac to drop or lose some coins, similar to Keeper Keepers.


  • They have 4 different appearances, though this is purely cosmetic.
  • Added in Afterbirth † 2 Greed Gapers may rarely replace the Shopkeeper in Shop Shops.
  • Added in Afterbirth † / Removed in Repentance 2-4 Greed Gapers have a chance to appear in Treasure Room Treasure Rooms.
  • Added in Repentance Greed Gapers no longer appear in Treasure Rooms; layouts that used to contain them now contain Bulb Bulbs. They can, however, appear in Ultra Secret Room Ultra Secret Rooms.

Deep Gaper[]

Added in Repentance

Deep Gapers are initially hidden and emerge from the floor once all initial enemies in the room have been killed. Deep Gapers walk towards Isaac slightly faster than Gapers after emerging and deal contact damage.


  • This enemy has 14 design variants, 7 for Downpour Downpour and 7 for Dross Dross. These variants are purely cosmetic with the exception of one that has a Small Leech Small Leech stuck to its head, which will detach from it and chase Isaac when the Deep Gaper is killed.


Added in Repentance

Blurbs walk slowly towards Isaac, dealing contact damage. After taking some damage or getting close to Isaac, they fire a chaotic burst of tears at him and chases Isaac at the speed of Frowning Gapers, attempting to deal contact damage. They have a high chance to turn into Pacer Pacers or Gusher Gushers upon death.

They will still spit out their projectiles if killed in an instant with high damage, firing towards Isaac even if he is not within targeting range.


Added in Repentance

Wraiths walk towards Isaac slightly faster than Gapers, dealing contact damage. They are invisible and can only be seen through the reflection they cast in the water, or the ripples they make as they walk. The occasional lightning strikes in Downpour will also make them briefly visible.


  • They are visible in the Mirrored World, but their reflections will be invisible instead, appearing when lightning strikes.
  • The occasional lightning strikes in Downpour Downpour will briefly render them visible.

Rotten Gaper[]

Added in Repentance

Rotten Gapers chase Isaac but have different behaviors depending on their appearance, and each has a different subtype (10.3.x).

ID Image Specifications
10.3.1 Rotten Gaper.png Fairly high speed, same as a Frowning Gaper Frowning Gaper.
10.3.2 Rotten Gaper 2.png Significantly higher speed, slightly less than a Gazing Globin Gazing Globin.
10.3.3 Rotten Gaper 3.png Moderate speed; spawns a Small Maggot Small Maggot every 2 seconds, but no more than 6 at a time.
10.3.4 Rotten Gaper 4.png Moderate speed, same as a Gaper Gaper.
10.3.5 Rotten Gaper 5.png Moves similarly to Lust Lust, gradually gaining momentum, and moves very fast. Doesn't try to run into Isaac, instead tries to 'orbit' around him.

Dead Isaac[]

Added in Repentance

Dead Isaacs are enemies exclusively spawned by Mother Mother as part of one of her attacks. They are summoned from the bottom of the arena and will walk directly upward (ignoring Isaac completely), dealing contact damage. Once they reach Mother, she swipes at them, killing them, releasing a burst of blood shots, and launching their corpses towards Isaac. After a while, she ends this attack by slamming down both hands, which causes a small rock wave to appear beneath any remaining Dead Isaacs, launching them up into the air.


  • Due to Dead Isaac only being encountered via one attack, it is possible to go multiple runs without finding them. They are required in order to complete the Bestiary.


Added in Repentance

Twitchies are a Gaper/ Trite Trite hybrid that alternate between chasing Isaac and rapidly leaping at him, dealing contact damage. They leap at Isaac 1-3 times before returning to chasing him on foot, and their leaps can target him from almost across an entire normal-sized room. They can leap to Isaac's current position, or where Isaac is heading, and can also leap away to dodge incoming fire.

Level 2 Gaper[]

Added in Repentance

Level 2 Gapers walk toward Isaac (faster than Gapers but slower than Frowning Gapers), dealing a full Heart of contact damage. They split into a Level 2 Horf Level 2 Horf and Level 2 Gusher Level 2 Gusher upon death.



  • When Head of the Keeper Head of the Keeper is picked up as Keeper Keeper, he will look similar to the Greed Gaper.
  • The appearance of Cyclopias is reminiscent of the fatal birth defect of the same name, which is characterized by the failure of the embryonic prosencephalon to properly divide the orbit of the eyes into two cavities.
  • A Stoney Stoney makes the same sound as a Large Champion Gaper.
  • Frowning Gapers and Nulls don't make noises until they open their eyes.
  • Greed Gapers are also known as Greedlings, a name given by a card of it from The Binding of Isaac: Four Souls, although it's seldom referred to as a "Greedling" by players.
  • Gapers have among the most variations of any 'family' of monster.
  • Blurbs spawned outside of Downpour Downpour will be skin-toned.
  • Wraiths spawned in rooms without water will appear translucent.
  • In Antibirth, Deep Gapers were referred to as Tidal Gapers.
  • Despite being a hybrid with a Trite, Twitchies aren't affected by Bursting Sack Bursting Sack due to being categorized as a Gaper variant.


Bug Bug! If a Dark-Red champion Frowning Gaper does not become a Pacer Pacer or Gusher Gusher and regenerates, the head won't appear until it sees Isaac. The same goes for a Gaper, however the head won't appear at all.
Bug Bug! If an Explosivo Explosivo tear is stuck to a Nulls when it becomes invisible, the tear will fall to the ground.
Bug Bug! If a Champion Gaper is killed and it turns into a Pacer Pacer or Gusher Gusher, it will no longer be a champion.