??? (Boss)

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 Chest, accessed by defeating Isaac in the Cathedral while holding The Polaroid, which is always dropped by Mom 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 Flies, Moters, or Pooters 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 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

??? in-game.
??? in his second phase.
??? in his third phase.
??? as one of Delirium's forms.
???'s boss portrait in the GFVELLLL seed as well as the G Fuel themed daily challenge.
??? as a can of G Fuel.
Trophy spawned after defeating G Fuel ??? in the daily challenge.
???'s old boss portrait prior to Repentance.

Unlockable Achievements

I RULE! - Defeat ??? or The Lamb, defeat Satan as Isaac, and unlock The Negative
Defeat ??? or The Lamb, and defeat Satan as Isaac
Defeat Mega Satan and unlock The Negative.

Backasswards - Defeat ??? or The Lamb
Defeat Mega Satan and unlock The Negative.

Ultra Hard - Defeat ??? or The Lamb. Possession of The Polaroid / The Negative is required, barring getting to Dark Room through a Sacrifice Room.
Defeat Mega Satan and unlock The Negative.

The D20 - Defeat ??? as Isaac.

Celtic Cross - Defeat ??? as Magdalene.

Cain's Eye - Defeat ??? as Cain.

The Left Hand - Defeat Ultra Pride as any character, or ??? as Judas.

Fate - Defeat ??? as ???.

Sacrificial Dagger - Defeat ??? as Eve.

Blood Penny - Defeat ??? as Samson.

Abaddon - Defeat ??? as Azazel.

Store Credit - Defeat ??? as Lazarus.

Mysterious Paper - Defeat ??? as Eden.

The Body - Defeat ??? as The Lost.

Cambion Conception - Defeat ??? as Lilith.

Deep Pockets - Defeat ??? as Keeper.

Locust of Famine - Defeat ??? as Apollyon.

Jaw Bone - Defeat ??? as The Forgotten.

Blessed Penny - Defeat ??? as Bethany.

Birthright - Defeat ??? as Jacob and Esau.

Something wicked this way comes! - Defeat ??? as 3 different Characters.

Something wicked this way comes+! - Defeat ??? as 6 different Characters.

Godhead - Earn all 5 / 9 / 10 / 12 Completion Marks on Hard mode as The Lost.

Mom's Lock - Defeat Isaac, ???, Satan, and The Lamb as Tainted Isaac.

Holy Crown - Defeat Isaac, ???, Satan, and The Lamb as Tainted Magdalene.

Gilded Key - Defeat Isaac, ???, Satan, and The Lamb as Tainted Cain.

Your Soul - Defeat Isaac, ???, Satan, and The Lamb as Tainted Judas.

Dingle Berry - Defeat Isaac, ???, Satan, and The Lamb as Tainted ???.

Strange Key - Defeat Isaac, ???, Satan, and The Lamb as Tainted Eve.

Temporary Tattoo - Defeat Isaac, ???, Satan, and The Lamb as Tainted Samson.

Wicked Crown - Defeat Isaac, ???, Satan, and The Lamb as Tainted Azazel.

Torn Pocket - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lazarus.

Nuh Uh! - Defeat Isaac, ???, Satan, and The Lamb as Tainted Eden.

Kid's Drawing - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lost.

The Twins - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lilith.

Keeper's Bargain - Defeat Isaac, ???, Satan, and The Lamb as Tainted Keeper.

Cricket Leg - Defeat Isaac, ???, Satan, and The Lamb as Tainted Apollyon.

Polished Bone - Defeat Isaac, ???, Satan, and The Lamb as Tainted Forgotten.

Expansion Pack - Defeat Isaac, ???, Satan, and The Lamb as Tainted Bethany.

RC Remote - Defeat Isaac, ???, Satan, and The Lamb as Tainted Jacob.

Notes

??? cannot teleport during his third phase if he is slowed (e.g. using Stop 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.
??? is fought as the first phase of Hush with identical behavior and music, only using a different sprite. The Hush version also has half the HP.
Delirium's ??? form is one of its only forms that don't have any melted features, along with both of the Angels.
Blighted Ovum, Big Horn, Triachnid, Isaac, and ??? are the only bosses whose portraits were completely changed in Repentance (beyond simply adding more detail). Of these, only Triachnid, Isaac, and ??? didn't receive new sprites.
- Isaac 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.