Monsters

Monsters are many creatures encountered throughout the game.

Most monsters (with few exceptions) will damage Isaac by either touching him or shooting him with shots. Along with normal varieties of monsters, Champion versions of monsters can be found lurking about. These monsters are often like normal monsters, but have a color tint or size change and drop basic Pick Ups (or rarely, a Chest) upon death. There are also Champion version of Bosses.

Monster List

Monster	Description	WotL DLC
Black Fly	Tiny black flies that do not hurt Isaac upon touch.
Attack Fly	Red Flies that follow Isaac and deal touch damage.
Moter	Follows Isaac, similar to Attack Flies. Will split into 2 Attack Flies upon death.
Eternal Fly	Invulnerable Fly that circles Corny Poop, Holy Leeches or Hangers.	✔
Pooter	Slow-moving flies that fire single blood shots at Isaac. Pooters do not deal touch damage.
Fat Fly	Alternate version of Pooters. Fires 2 shots in a V-formation and does not deal touch damage.	✔
Boom Fly	Flies around the room diagonally, dealing touch damage and exploding with a large blast radius upon death.
Red Boom Fly	Flies around the room diagonally, dealing touch damage and exploding into 6 directional blood shots upon death.
Sucker	Flies slowly towards Isaac, exploding into 4 projectiles in a + formation upon death.
Spit	Flies slowly towards Isaac, exploding into an IPECAC shot upon death which targets other Spits in the room, or Isaac.	✔
Spider	Moves erratically around the room, damaging Isaac by touch.	✔
Big Spider	Moves erratically around the room, splitting into two Spiders upon death.	✔
Trite	Quickly jumps towards Isaac with high distance.	✔
Boil	Stationary enemy that shrinks upon being hit. Will quickly swell up if not killed in time. Fires multiple short-ranged blood projectiles when fully swollen.
Gut	Stationary enemy that shrinks upon being hit. Will quickly swell up if not killed in time. Fires an IPECAC shot at Isaac when fully swollen.	✔
Sack	Stationary enemy that shrinks upon being hit. Swells up slower than Guts and Boils. Spawns a Spider when fully swollen.	✔
Walking Boil	Mobile Boil that cannot shrink, but has a finite amount of health. Fires short-ranged blood shots with varying sizes at a reduced fire rate.	✔
Walking Gut	Mobile Gut that cannot shrink, but has a finite amount of health. Fires IPECAC shots at a reduced fire rate.	✔
Walking Sack	Mobile Sack that cannot shrink, but has a finite amount of health. Spawns Spiders.	✔
Mulligan	Harmless enemy that walks around the room, avoiding Isaac. Will spawn multiple flies upon death.
Mulligoon	Harmless enemy that walks around the room, avoiding Isaac. Will drop a Troll Bomb upon death.
Mulliboom	Walks towards Isaac, exploding with a large blast radius upon death or upon touching Isaac. The explosion does a half-heart of damage instead of the regular full heart.	✔
Hive	Walks around the room, avoiding Isaac while spawning Attack Flies. Spawns a large number of Flies upon death.
Swarmer	Slowly floats around the room, spawning a Pooter upon taking damage. Spawns a large number of Flies upon death.	✔
Hopper	Jumps around the room slowly, damaging Isaac by touch.
Flaming Hopper	Jumps around the room quickly, covering a large distance, similar to Trites.
Leaper	Jumps around the room quickly, but not as fast as F. Hoppers. Occasionally jumps high into the air, dropping down elsewhere while firing 4 blood shots in a plus pattern.
Pacer	Walks aimlessly around the room. Usually spawned after killing a Gaper/Frowning Gaper.
Gusher	Walks aimlessly around the room, firing extremely short-ranged blood projectiles from its head. Usually spawned after killing a Gaper/Frowning Gaper.
Gaper	Walks towards Isaac, dealing contact damage. Usually turns into a Pacer or Gusher upon death.
Frowning Gaper	Walks towards Isaac, dealing contact damage. Usually turns into a Pacer or Gusher upon death.
Gurgle	Slowly walks towards Isaac, firing short-ranged IPECAC shots at him. Has much more health than regular Gapers.	✔
Mr. Maw	Walks towards Isaac, quickly launching its head, still attached to its body by a cord. Turns into a Maw or Pacer upon death.
Horf	Stationary enemy that fires medium ranged blood shots at Isaac.
Maw	Floats towards Isaac, firing fast-moving blood shots.
Red Maw	Floats towards Isaac faster than regular Maws, exploding into 4 blood shots in a plus pattern upon death. Does not fire any shots.
Psychic Maw	Alternate version of a Maw, has an Eternal Fly circling it. Fires large, purple homing shots at Isaac.	✔
Globin	Walks towards Isaac, dealing one heart of contact damage. Turns into a pile of goo after taking enough damage, where it can be killed. Will regenerate after a short amount of time if not killed quickly.
Gazing Globin	Quickly walks towards Isaac, dealing one heart of contact damage. Turns into a pile of goo and slides away after taking enough damage, where it can be killed. Will regenerate after a short amount of time if not killed quickly.
Knight	Moves erratically around the room. Can only be damaged from behind.
Selfless Knight	Moves erratically around the room, charging at Isaac at very high speed. Can only be damaged from behind.
Mask + Heart	Invulnerable mask with a slow-moving Heart. Functions similarly to a Knight. The Heart fires 4 blood shots in a plus pattern when Isaac gets near. Killing the Heart will automatically kill the Mask.	✔
Clotty	Moves around the room, firing 4 blood shots in a plus pattern.
Clot	Moves around the room, firing 4 tar shots in an X pattern.
I. Blob	Moves around the room, firing 8 shots in all directions.	✔
Maggot	Aimlessly moves around the room, damaging Isaac by contact.
Charger	Slowly moves around the room, charging at Isaac when he gets in its line of sight.
Spitty	Slowly moves around the room, firing a single long-ranged blood shot when Isaac gets in its line of sight.
Brain	Crawls around the room, leaving a trail of red Creep that does one heart of damage.
MemBrain	Slowly moves around the room, occasionally hopping and firing 8 large blood shots in all directions. Will split into 2 Brains upon death.
Guts	Attaches itself to a wall or obstacle, such as a Rock, rolling around the room.
Mama Guts	Slowly moves around the room, occasionally hopping and firing 8 large blood shots in all directions. Will split into 2 Guts upon death.	✔
B. Licker	Attaches itself to other B. Lickers, erratically moving around the room, similar to Larry Jr.	✔
Para-Bite	Moves towards Isaac. Can burrow underground and reappear elsewhere.
Fred	Fires an IPECAC shot at Isaac. Will hop out of the ground and burrow elsewhere, firing 4 blood shots in an X pattern while doing so.
Lump	Fires 3 fast-moving blood shots at Isaac when he gets in its line of sight. Will burrow underground and reappear elsewhere after firing its shots.
Leech	Quickly charges towards Isaac when he gets in its line of sight.
Kamikaze Leech	Quickly charges towards Isaac when he gets in its line of sight. Explodes with a large blast radius upon death.
Holy Leech	Quickly charges towards Isaac when he gets in its line of sight. Explodes with a large blast radius upon death. Has an Eternal Fly circling it.	✔
Host	Invulnerable stationary enemy. Raises its head up when Isaac gets close, revealing a fleshy stem that can be damaged. Upon raising its head, it will fire 3 blood shots and lower its head again.
Red Host	Stationary enemy that can be damaged even when its head is lowered. Fires 5 blood shots instead of 3 when rising, and fires more frequently.
Vis	Charges up a Brimstone laser when Isaac gets in its line of sight.
Double Vis	Charges up a Brimstone laser which fires from both sides when Isaac gets in its line of sight.	✔
Chubber	Fires a Little Chubby-like familiar that deals one heart of damage when Isaac gets in its line of sight.	✔
Poky	Moves around the room, damaging Isaac by contact.
Slide	Quickly slides towards Isaac when he gets in front of it.	✔
Eye	Quickly fires a Technology-like laser at Isaac.
Bloodshot Eye	Quickly fires a Brimstone-like laser at Isaac.
Dople	Copies Isaac's movements, and fires tears at the same time as him.
Evil Twin	Copies Isaac's movements, and fires tears at the same time as him.
Embryo	Aimlessly hops around the room, damaging Isaac by contact damage.
Baby	Fires a single blood shot at Isaac. Can teleport and reappear elsewhere.
Angelic Baby	Fires 3 blood shots at once at Isaac, has much more health than regular Babies.	✔
Keeper	Hops around the room, firing 2 blood shots in a V formation at Isaac.	✔
Hanger	Floats around the room, firing 3 blood shots at Isaac. Has an Eternal Fly circling it.	✔
Stone Grimace	Stationary and invulnerable monster that fires a fast-moving blood shot at Isaac. Stops firing when room is cleared.
Vomit Grimace	Stationary and invulnerable monster that fires an IPECAC shot at Isaac. Stops firing when room is cleared.	✔

Monster List by Floor

The Depths
Baby Boil Boom Fly Brain Globin Guts Hive Host Knight Selfless Knight (rare) Leaper Leech Embryo Kamikaze Leech (rare) Mr. Maw Moter MemBrain (very rare) Pooter Psychic Maw (rare) Spiders Vis Bosses up to the Caves

The Womb
I.Blob (very rare) Brain Dople Eye Fly Fred Leech Holy Leech (uncommon) Host Lump Embryo (uncommon) Membrain Para-Bite Poky Globin (uncommon) Guts Mr. Maw (uncommon) Spider (uncommon) Vis
Bosses up to the Caves
A pair of complete Blastocysts or 4 'second stage' Blastocysts may spawn.

Utero
Angelic Baby (uncommon) Mama Guts Buttlicker Dople Fred Guts Gurdy Jr. Mask + Heart Heart Para-Bite Spider (uncommon)
Bosses up to the Caves
A pair of complete Blastocysts or 4 'second stage' Blastocysts may spawn.

Sheol
I.Blob (very rare) Leech (uncommon) Kamikaze Leech (note: spawned in the battle with Satan) Holy Leech (uncommon) Headless Horseman's Head (2-3) Selfless Knight Dople Evil Twin Sucker Spit Globin (rarely) Spider
Two Greeds and a whole Fistula.
All bosses up to the Depths as well as Death, The Fallen, Headless Horseman, Loki (commonly 2) and Lokii
Some bosses will appear in pairs of themselves, such as Gemini.
Gurdy will not appear.
*Rarely monsters from early levels, such as a non-aggressive fly will spawn in rooms by themselves. This might be a bug.

Cathedral
Angelic Baby I.Blob Clot Holy Leech Spit Spider
All bosses up to the Depths as well as the Headless Horseman, Loki (commonly found as a pair, complete with Poky) and Lokii

Monster replacements

Some monsters in the Binding of Isaac are randomly replaced by similar counterparts. These can either be "champion" versions that are recolored or completely different enemies with modified attacks.

Champion Enemies

Normal enemies can be recolored to become champion enemies, which by default have twice as much HP as their normal counterparts. Similarly, some champion enemies are able to deal full heart damage regardless of the level. Champion enemies will always drop a free pickup when killed.

Enemy Variants

These variants may replace normal enemies in a room

Some variants will additionally count as champion enemies if encountered on certain floors. For example, Bloodshot Eyes, Selfless Knights, Kamikaze/Holy Leeches and the Evil Twin can be considered champions when encountered in the Womb or earlier and will drop a pickup when killed.

Replacement/Variation Chart
may be replaced by or may be replaced by may be replaced by may be replaced by may be replaced by may be replaced by or may be replaced by or may be replaced by may be replaced by or may be replaced by may be replaced by may be replaced by may be replaced by may be replaced by or may be replaced by may be replaced with may be replaced with may be replaced with

Gallery

<gallery> Page 35.jpg|Various monsters in the Artbook. (Scans provided by Kisspower12) Page 37.jpg Page 38.jpg