Binding of Isaac: Rebirth Wiki

This article is about the boss at the end of The Chest. For the character, see ??? (Character). For other uses, see ??? (Disambiguation).

??? is the boss of ChestChest, accessed by defeating Boss Isaac ingameIsaac in the CathedralCathedral while holding Collectible The Polaroid iconThe Polaroid, which is always dropped by Boss Mom ingameMom after defeating Isaac five times. He is a posthumous version of Isaac, and the final boss of Ending 14.

Behavior[ | ]

??? lies on the ground in the middle of the room and does not begin attacking until he takes damage.
During all three of ???'s phases, he performs similar attacks to Isaac, but at a faster pace. He also shoots multiple projectiles in the player’s direction at fixed intervals. After taking enough damage, he begins to shoot double and triple projectiles.

  • Each projectile has a chance of having a homing effect.

Phase 1[ | ]

??? remains stationary on the ground and performs the following attacks:

  • Shoots 7-8 rapid-fire lines of projectiles in all directions that expand outwards. After taking enough damage, these lines curve while travelling.
  • Shoots 8 lines of 2 projectiles in all directions that expand outwards. Each line consists of one normal projectile and one homing projectile. After taking enough damage, these lines curve while travelling.
  • After taking enough damage, ??? summons Attack FlyAttack Flies, MoterMoters, or PooterPooters that orbit around himself.
    • Pooters have a farther orbit than the other flies.
    • Attack Flies spawned from Moters chase Isaac instead of orbiting ???.

Phase 2[ | ]

2 Eternal FlyEternal Flies that can block tears begin to circle ???, who stands up but remains stationary and performs the following attacks:

  • Continues to spawn orbiting flies.
  • Fires 4 homing projectiles in a lop-sided X pattern.
  • Fires 8 homing projectiles in all directions.

Phase 3[ | ]

??? grows a pair of angelic wings and is no longer stationary, slowly drifting towards Isaac and performing the following attacks:

  • Spawning orbiting eternal flies (with increasing frequency compared to the previous phase).
  • Teleporting to a position in front of the player - predicting their movements and attempting to cut them off. ??? will teleport directly on top of the player if the player is stationary.
  • Shooting 2 projectile patterns from the first phase.

Gallery[ | ]

Unlockable Achievements[ | ]

Notes[ | ]

  • ??? cannot teleport during his third phase if he is slowed (e.g. using Collectible Stop Watch iconStop Watch).

Trivia[ | ]

  • ??? was added in the Wrath of the Lamb DLC for the original The Binding of Isaac.
  • The music that plays during this boss fight is titled Ascension.[1] The term "ascend" is typically used in religion as the act of one's soul rising to Heaven.
  • ???, along with Isaac, flies away upon defeat and does not "die".
  • ??? is commonly referred to as the 'blue baby' by the Binding of Isaac community, as well as Steam Achievements.
  • (except in Rebirth) ??? is fought as the first phase of (except in Rebirth) Boss Hush ingameHush with identical behavior and music, only using a different sprite. The Hush version also has half the HP.
  • (in Afterbirth † and Repentance) Delirium's ??? form is one of its only forms that don't have any melted features, along with both of the Angels.
  • (in Repentance) Boss Blighted Ovum ingameBlighted Ovum, (in Afterbirth † and Repentance) Boss Big Horn ingameBig Horn, Boss Triachnid ingameTriachnid, Boss Isaac ingameIsaac, and ??? are the only bosses whose portraits were completely changed in Repentance (beyond simply adding more detail). Of these, only Boss Triachnid ingameTriachnid, Boss Isaac ingameIsaac, and ??? didn't receive new sprites.
    • Boss Isaac ingameIsaac and ???'s portraits were changed to match their appearances on the transition screen between levels. This was also the case in the original Flash game.
  • ??? has a unique sprite when encountered in the GFVELLLL seed as well as the limited time G Fuel themed daily challenge.
    • This sprite was added in celebration of the release of "Isaac's Tears" flavored G Fuel.
  • ??? Is also a reference to BlueBaby, Edmund's Newgrounds name.

References[ | ]