Binding of Isaac: Rebirth Wiki

Disambig.png This article is about the fly enemies. For other uses, see Fly (Disambiguation).

Flies are enemies that buzz around the room randomly, but slowly hover towards Isaac. They cannot damage Isaac at all, even by touch, making them completely harmless. However, they can turn into Pooter Pooters if they fly around Poop Poop for too long.

Along with monsters like the Gaper Gapers and Spider Spiders, Flies are one of the most commonly-encountered monsters and appear in numerous different types.


Attack Fly[]

Attack Flies are red and black flashing flies that will chase Isaac dealing contact damage.

Attack Flies turn into regular Flies if Isaac has Skatole Skatole. However, they take a small amount of time to convert into Flies, so it is possible for Isaac to be damaged if the player is not careful.


  • The Duke of Flies The Duke of Flies can spawn larger versions of Attack Flies that have 10 base HP.
  • Gurdy Gurdy can spawn weaker versions of Attack Flies that only have 3 base HP.

Ring Fly[]

Ring Flies are a new addition to Rebirth. They are pink flies that, upon entering the room, will cluster together into a circular formation and orbit rapidly while moving towards Isaac. They will hold formation even as flies are destroyed. The maximum amount of flies per formation is 10.


  • Ring Flies are not affected by Strange Attractor Strange Attractor and will continue to stay within their current circular formation.


Moters appear as two conjoined Attack Flies. They behave similarly to regular Attack Flies, but split into two Attack Flies upon being killed. The directions the Attack Flies will split off is parallel to Isaac (vertical if Isaac is to either side, and horizontal if he is above or below).


  • If Isaac has Skatole Skatole or kills a Moter fast enough, it will not split into two Attack Flies.

Eternal Fly[]

The Eternal Fly is a white-colored fly that can be found on any floor in the game. They usually circle Corny Poop Corny Poop or enemies like Holy Leech Holy Leeches and Hanger Hangers, and will not stop circling them until their hosts are destroyed. Before that, they will deal damage to Isaac if he touches them, and they are completely immune to all forms of damage. When their hosts are destroyed, they convert into a modified version of an Attack Flies that regenerates health and can be killed if walked into. Eternal Flies circling Corn Poop do not need to be killed to clear a room.


Dart Fly[]

Added in Afterbirth

Dart Flies are similar to regular Attack Flies, but attempt to predict Isaac's movements and cut him off.


Added in Afterbirth

Swarms are similar to regular Attack Flies, but appear in tightly-packed clusters.


  • If a Swarm is somehow separated from its group, it quickly moves back to its group when it is able to.

Hush Fly[]

Added in Afterbirth

Hush Flies are mainly spawned by Hush Hush and behave somewhat similar to Ring Flies, but do not fly towards Isaac and remain in a fixed path. Unlike Ring Flies, Hush Flies can form other shapes such as polygons. When spawned by Hush they can also orbit it, form a pattern and travel in a straight path, or form a pattern and chase after Isaac.

Hush Flies have a brief period of invincibility when Hush spawns them, making them appear to have more health than they actually have.


  • Hush Flies are not affected by the Beelzebub Beelzebub transformation.
  • Added in Afterbirth † Hush Flies can also spawn outside of the Hush fight in some rare rooms.
  • Added in Repentance They can also appear in ??? ??? with the use of Red Key Red Key.

Army Fly[]

Added in Repentance

Army Flies chase Isaac, moving in the cardinal directions as they do so. If there are other Army Flies in the room, they will form a single-file line while chasing Isaac.


Added in Repentance

Willos circle a set distance around Isaac, moving with him perfectly, and firing shots inwards towards him; only one can fire at a time, and the one about to fire telegraphs this by flashing rapidly just beforehand. They circle quickly at even intervals, and can be hard to hit. If there is a Fire Place within the room, they can be guided into it; making this an efficient method of tackling this enemy. They do not deal contact damage.


  • Min-Min Min-Min can spawn these; some of them behave normally, while some pop out of the ground, launch a volley of shots at Isaac, and disappear back into the ground.
  • Mullighoul Mullighouls spawn these occasionally, and spawn 2 more when they die.

Ultra Famine Fly[]

Added in Repentance

Ultra Famine Flies are flies spawned by Ultra Famine Ultra Famine that charge at Isaac on a delay. They come in 3 sizes- small, medium and large.

Ultra Pestilence Fly[]

Added in Repentance

Ultra Pestilence Flies are flies spawned by Ultra Pestilence Ultra Pestilence that swarm around him, blocking shots and dealing contact damage. They also can be spawned by the Ultra Pestilence Fly Ball Ultra Pestilence Fly Ball in Ultra Pestilence's 2nd phase. They come in 3 sizes- small, medium and large.



  • The Black Fly has the lowest health of any enemy in the game, tied with the Added in Afterbirth Corn Corn and Added in Repentance Drip Drip.
  • Eternal Flies were first added to the Wrath of the Lamb DLC for the original Binding of Isaac game.
  • There is a variant of Moters in the Eternal Edition of the original The Binding of Isaac that resembles a ball of 4 Attack Flies, or 2 Moters stuck to each other. This enemy does not appear in Rebirth, likely due to being added in said Eternal Edition update that was added a while after the release of Rebirth.
  • In a Q&A Reddit thread by Edmund McMillen, Edmund confirmed that the species of flies in The Binding of Isaac are house flies and botflies.[1]
  • The name Willo might be a reference to Will'o the Wisps, atmospheric ghost lights seen at night, especially over bogs, swamps or marshes.
  • Although Army Flies were known to be revealed during Repentance's first PAX session, it was in fact first revealed in the latest blog of a now-canceled update for the Antibirth mod back in December 21st, 2017.