The Binding of Isaac Wiki

Peep is a boss who can be fought in The Caves, and The Catacombs in the Wrath of the Lamb DLC.


Before Peep does an attack, he will give a signal as to what attack he's going to do.

  • A spray attack that sends ten urine projectiles flying out in a radial burst pattern. This is signaled by Peep smiling and bringing his hands to his face.
  • A jump that brings him crashing down on the location he last saw the player standing in. This is signaled by Peep smiling and throwing his arms wide.
  • Oozing out glowing puddles of yellow creep that deal 1 heart damage if Isaac stand in them. These go away after 5–6 seconds, and don't affect characters with flight. This is signaled by Peep frowning and slightly shrinking, along with him making a burping sound.

Peep's Eye[]

Additionally, at 66% and 33% health, he'll detach one of his eyeballs and set it to bouncing around the room in diagonal lines. The eyeballs cannot be damaged at all until Isaac kill Peep himself, so don't waste your time shooting. They leave behind a purely cosmetic blood trail but do 1/2 heart of damage on touch normally and 1 if Isaac is fighting him in The Womb.


The following strategies have proven to work against Peep:

  • The biggest problem in dealing with Peep is the radial burst. Isaac can dodge behind rubble piles (or hover above them if Isaac has flight) to avoid the spray if there are any, but often Isaac will be facing him in an empty room. Isaac's best option there is to stay well away on his left or right side, moving back and forth between opposite sides of the room whenever he launches. At maximum range, Isaac should be able to dodge the burst with just a little movement up or down to put him between shots. Don't forget to watch for the eyeballs, they can sneak up on Isaac if he's focusing on Peep for too long.
  • Because this fight requires so much dodging, items that require careful aim are best avoided. With good timing, bombs/Mr. Boom can be used to catch Peep when he lands after his jump. Spoon Bender or I The Magician can help greatly in keeping Isaac's shots more or less on target while you dodge the pee spray. Range increasing items will give Isaac more room to maneuver; conversely, range reducing pickups like Number One or My Reflection will make his life harder in this fight. Continuous, sustained fire from maximum range is the order of the day here. Peep's eyes are also slowed down by Skatole, making them easier to dodge.
  • The Spider's Bite's slowing tears effect affect Peep in an unusual way. While slowed, Peep's jump will send him straight up into the air, then right back to where he launched from (as opposed to Peep launching and then landing at the location he last saw the player). This makes his pattern very predictable, as Peep can be kept at one spot indefinitely, with the player only occasionally needing to move to dodge the pee spray and eyeballs.
  • Despite being able to jump to great heights, he can't move over rocks while airborne. This allows Isaac to take cover behind or over rocks, but it can also mean that predicting where Peep lands can be tricky without following the urine trail he leaves while he's airborne.


  • If II The High Priestess reduces Peep's health below 33% health before his first eye comes loose, only one will be spawned. Graphically, he will have both eyes missing, but Isaac will only have to dodge one for the remainder of the encounter.

Champion Variants[]


Peep Blue

Both of Cyan Peep's eyes are out right from the beginning of the fight. Otherwise, he behaves the same as the original version.


Peep Yellow

The Yellow Peep is physically smaller and behaves like the original, but constantly leaves a urine-trail, even while in mid-air during a jump, which hurts the player if stepped on.


Eternal Peep

The Eternal Peep appears exclusively in Hard Mode, which was added in the Eternal Edition update.

He now has 6 eyes, each eye comes out every time he loses 1/7 of his maximum HP. Note that his eyes are no longer invulnerable and can be destroyed.


  • Peep appears in the demo.
  • Peep has the second highest amount of HP among all bosses in Caves and Catacombs (the highest being Gurdy).
Page 17

Peep in the artbook.

  • Peep was alternatively known as Slug Boy, Sluggy, and Pisser in the artbook. At one point during development, Peep's early design resembles more like a slug than an obese humanoid.
  • His name is pronounced Pee-pee as a double entendre, for his two sources of damage are urine and his eyes.
  • Peep's bulging eyes are a reference to Exophthalmos, a disease that causes the person's (including animals) eyes to bulge.
  • If his eye kills Isaac, a Boom Fly will appear on Isaac's Last Will. This is due to the fact that his eyeballs share the same AI as a Boom Fly.
  • If his urine trail kills Isaac, a Brain will appear on Isaac's last will.
    • This is the case with all forms of creep.
  • The two invincible eyeballs that detach from Peep may be a reference to Gleeok from The Legend of Zelda, a boss which would spawn two invincible heads when damaged.
  • Peep is crying blood in his death animation. The bloody tears were removed in the Rebirth remake.


  • Since Peep's eyes share coding with the Boom Fly, his eyes may explode when Peep dies or even sometimes shoot six blood projectiles in the same manner of a Red Boom Fly and their movement will be slowed by Skatole.
  • If the character stand right in front of the boss door he will sometimes push them out of the boss room if he jumps on them.


Standard Bosses Dukeofflies fullThe Duke of FliesGemini fullGemini260x185-400px-Monstro.svgMonstroLarryjr fullLarry Jr.FistulaFistulaGurdy fullGurdyPeep FullPeepChubChubLoki fullLokiScolex fullScolexBlastocyst fullBlastocystTheFallen FullThe Fallen

Wrath of the Lamb DLC: 260x200-400px-Widow3WidowPin cleanPinMask of InfamyMask of InfamyGurdjrGurdy Jr.VS DaddyLonglegsDaddy Long Legs

Posthumous Bosses 285x230-MonstroII fullMonstro II

Wrath of the Lamb DLC: The HuskThe Husk260x220-The Hollow2The Hollow250x200-Teratoma.TeratomaLokii cutoutLokiiBlighted ovumBlighted OvumCarrionqueenThe Carrion QueenThe WretchedThe WretchedBc BloatThe Bloat

Alternate Bosses 287x265-Steven FullsizeStevenChub fullC.H.A.D.Gish fullGish

Wrath of the Lamb DLC: 200x300-400px-Triachnid boss portraitTriachnid

Harbingers 220x287-Isaac Vs famine edited- noobletkFamineBC PestilencePestilenceBC WarWarVSDeathDeath230x200-Headless HorsemanHeadless Horseman

Wrath of the Lamb DLC: BC ConquestConquest

Final Bosses 250x250-400px-MomMomMoms Heart FullMom's Heart250x250-ITLIVEScutoutIt LivesSatan FullSatan

Wrath of the Lamb DLC: Bc isaacIsaacBC xxx???