Binding of Isaac: Rebirth Wiki

The Lost is a secret character.

The Lost starts with no health and cannot gain health by any means. Therefore, it will die from any damage taken.

3DS The Lost also starts with Collectible D4 iconD4 (if unlocked).

iOS The Lost also starts with Collectible D4 iconD4 (if unlocked) and spectral tears.

(except in Rebirth) The Lost can activate the button in Greed mode without taking damage, at the price of one less coin spawning in the next wave's reward.

The Lost can take devil deals and Black MarketBlack Market items for free.

  • (in Repentance) Devil deals and Black Market items are presented as choices. Taking one will despawn all other deals in the room.
    • This also applies to devil deals in the first room of the Dark RoomDark Room; only one of the devil deals spawned by the chests can be taken, regardless of how many chests have been opened.

Notes[ | ]

  • Resurrection items like Collectible Dead Cat iconDead Cat are extremely valuable to The Lost because they are effectively the only health-ups you can get.
  • Devil deals, while free, still count as making a deal with the devil and will prevent Angel RoomAngel Rooms from opening. Thus, a Credit CardCredit Card is still recommended, or getting (except in Rebirth)Collectible Chaos iconChaos to acquire angel room items (except broken key pieces).
  • Using the Collectible IV Bag iconIV Bag or a Blood Donation MachineBlood Donation Machine will instantly kill Character The Lost iconThe Lost even with the Holy Mantle.
  • Bedrooms are much more common as Character The Lost iconThe Lost due to its lack of health. While it cannot take advantage of the beds to heal, the guaranteed Crawl SpaceCrawl Spaces in clean Bedrooms can give more opportunities for items.
  • (in Rebirth and Afterbirth) If The Lost's Holy Mantle effect is lost while within a Curse RoomCurse Room, closing the game, starting it up, and then continuing the run will restore the Holy Mantle's charge, allowing The Lost to leave the room unharmed.
    • (in Repentance) The Lost can no longer restore his Holy Mantle by closing the game, starting it up, and then continuing the run.
  • (except in Repentance) Using the D4 at all is not recommended, as it will remove the Holy Mantle, making The Lost die in one hit.
  • (in Afterbirth and Afterbirth †) After reaching WombWomb, The Lost becomes slightly easier to play, because the invincibility frames from Collectible Holy Mantle iconHoly Mantle scale with the damage that would have been taken.
    • (in Repentance) Holy Mantle breaking only grants one second of invincibility frames, regardless of the damage source.
  • (in Afterbirth † and Repentance) Isaac will be replaced by The Lost upon starting a third victory lap; however, Victory Laps do not allow the unlocking of achievements.
    • (except in Repentance) Since the Lost's Holy Mantle isn't intrinsic, the Victory Lap Lost will always die from one hit unless the player has explicitly found the Holy Mantle.
  • (in Repentance) The Lost starts with Collectible Eternal D6 iconEternal D6, even before it's unlocked.
  • (in Repentance) The Lost's Holy Mantle effect is intrinsic to the character once unlocked, and it can't be rerolled.
    • Picking up another one does not double the effect.
    • Being innate, this Lost hp Holy Mantle effect is not shown in the pause menu.
  • (in Repentance) Though Devil deals and Black Market items are normally choices, there are three ways to fully or partially bypass this and collect multiple items anyway:

General Strategies[ | ]

Main article: The Lost (Strategy)
  • One of the biggest issues of having no health is that many items become completely useless: items that only give health ups, only become effective upon taking damage, or cost health to use provide no benefit to The Lost.
    • (in Repentance) This is alleviated by the Collectible Eternal D6 iconEternal D6 that The Lost starts with. Eternal D6 has a chance to destroy an item instead of rerolling it, which isn't bad if it's used on a useless item. In fact, on its own, it can only yield a net positive (such as by rerolling a useless item into something useful) or neutral result, such as generating another useless item or destroying it.
  • Trinkets and Items like (in Repentance)Brain WormBrain Worm that can home-in and target enemies even at a distance are invaluable early in the game, as you do not need to place yourself directly in the enemy's attack path and (except in Rebirth)The Lost's spectral tears pass through most obstacles.
  • The Lost's ability to fly and (except in Rebirth)have spectral tears makes it extremely useful to take advantage of obstacles.
  • Anything that grants an extra life (e.g. Collectible Dead Cat iconDead Cat, Collectible Guppy's Collar iconGuppy's Collar) is highly useful, allowing The Lost to take hits or safely use certain items that have a chance to kill him, such as (in Repentance)Collectible Damocles iconDamocles.
  • (in Repentance) Due to The Lost's ability to take 1 Devil Item for free, Devil Rooms and Angel Rooms become equally valuable, unless one is going for Mega Satan.

Item Interactions[ | ]

  • (in Repentance)Collectible Alabaster Box iconAlabaster Box: Alabaster Box does not gain charges from Black Hearts. Soul Hearts still function as expected.
  • (in Repentance)Collectible Birthright iconBirthright: Prevents items with the internal tag nolostbr from spawning. In practice, this automatically rerolls most items that aren't beneficial to The Lost, namely ones that only give health, flight, and/or spectral tears or activate upon taking damage.
  • (in Afterbirth † and Repentance)Collectible Brittle Bones iconBrittle Bones: Picking this item up will give a one-time +0.5 tears up ((in Repentance) +0.4 fire rate). This bonus is retained even if the item is later lost or rerolled.
  • Collectible Habit iconHabit: Collectible Holy Mantle iconHoly Mantle will not activate the Habit's effect, making it almost completely useless since the only way that can get its effect to activate is by receiving damage, which would effectively kill the Lost or consume any available extra lives. The same is true for any items that require taking damage.
  • (in Repentance)Collectible Heartbreak iconHeartbreak: The Lost has full benefit of the item. This lets him survive 4 extra hits, each hit adding 1 damage, and the 5th is fatal.
  • Collectible Whore of Babylon iconWhore of Babylon: As the Lost has no red hearts (he has half a soul heart), Whore of Babylon is constantly in effect, effectively changing into a damage and speed upgrade.

(except in Rebirth) Unlocking The Lost in Afterbirth[ | ]

The Lost is unlocked by dying in a Sacrifice RoomSacrifice Room while holding Missing PosterMissing Poster.

  • Looking for (except in Rebirth)Collectible Mom's Box iconMom's Box in shops makes finding the poster easier.
  • (except in Rebirth)Collectible Glitter Bombs iconGlitter Bombs, in conjunction with a large enough or infinite source of bombs (such as a (except in Rebirth) Golden BombGolden Bomb), have a small chance to drop trinkets, making it easier to find the poster.
    • (in Repentance) This method got nerfed: Collectible Glitter Bombs iconGlitter Bombs now have a cap on drops per floor.
  • It is possible to unlock The Lost while holding Mysterious PaperMysterious Paper, although the probability is small since it only has a 1/4 chance to imitate the Missing PosterMissing Poster. Collectible Dead Cat iconDead Cat and other resurrection items could be useful for extra attempts.
  • If Isaac happens to teleport away from the sacrifice room right as he dies, then he won't unlock The Lost.
    • (except in Rebirth) Sacrificing health for the 12th time in a row and onwards has a 50% chance to teleport you to the Dark RoomDark Room. Make sure Isaac has no more than 11 hearts before attempting to die in the sacrifice room.
    • (except in Rebirth)Sacrificing health for the 6th time in a row will have a 33% to teleport Isaac to the Angel RoomAngel Room. If Isaac loses his last sacrifice and gets teleported to the Angel Room, he will not unlock The Lost.

(in Rebirth) Unlocking The Lost in Rebirth[ | ]

The Lost is unlocked by dying 4 times in a row, each time with a certain character dying in a certain circumstance. Deaths must be completed consecutively in the order shown below. Seeds can be used on all but the final step.

  1. Character Isaac iconIsaac must die to a MulliboomMulliboom in Chapter 1.
  2. Character Magdalene iconMagdalene must die to her own BombBomb in Chapter 2.
  3. Character Judas iconJudas must die to Boss Mom ingameMom. Being killed by any monster spawned by Mom will spoil the entire attempt at unlocking The Lost.
  4. Finally, Character Azazel iconAzazel must die to Boss Satan ingameSatan. Being killed by any of the other enemies spawned by Satan or Boss The Fallen ingameThe Fallen will spoil the entire attempt at unlocking The Lost. Using Collectible The Bible iconThe Bible on Satan does not count as death from Satan. Furthermore, you cannot be killed by Satan's stomp in the third phase. You must die in his second phase.

The Lost will be unlocked after completing the steps shown above.

Notes on unlocking The Lost[ | ]

  • Multiple lives (for example, obtained by Collectible Dead Cat iconDead Cat) must be depleted before the intended death, as deaths while having extra lives do not count as a game loss.
  • It is highly suggested you do not take items or trinkets with a chance of reviving you after dying, such as Collectible Guppy's Collar iconGuppy's Collar or Broken AnkhBroken Ankh, as these can spoil your attempt if unprepared.
  • Having any mods installed that triggers the mod flag will make The Lost unobtainable. To fix this problem, all mods have to be removed.
  • The game cannot be won as any character required to unlock it when unlocking it.
  • Champion versions of monsters and bosses will count for the death criteria.
  • Runs can always be safely reset.
  • Mom's Foot's stomp counts as explosive damage, which makes Collectible Pyromaniac iconPyromaniac a problematic choice when trying to complete Step 3.
  • Picking the wrong character while unlocking him doesn't mess up the unlocking process.[1]
  • Quitting and Restarting the game in the middle of the unlocking process doesn't mess it up.[1]
  • Picking up Collectible Lazarus' Rags iconLazarus' Rags, Collectible Judas' Shadow iconJudas' Shadow, or Collectible Ankh iconAnkh should be avoided. These items will revive the current character as a different one and therefore prevent the current unlock-step from being fulfilled.
  • Exploit: If you die during a required run, but hit the "start" button just as you die and reset before it shows Isaac's Last Will, it will not count as a death that spoils the run; instead, it counts as a restart.

File Manipulation[ | ]

By changing a file parameter, an unsuccessful try can be undone:

  1. Backup the file Options.ini found in the Documents\My Games\Binding of Isaac Rebirth by making a copy of it in the same folder.

Open the original file with Notepad and change the SteamCloud parameter in it to 0. This will disable Steam Cloud gamesaves synchronization.

  1. After an unsuccessful try, delete the original file and rename the backup copy with the name of the original file: Options.ini
  2. Repeat steps 1 after each successful run until you unlock The Lost.
  3. When finished, open the original file and restore the SteamCloud parameter in it to 1. This will enable Steam Cloud gamesaves synchronization again.

Helpful Seeds For Rebirth[ | ]


PC Normal mode only GPE3 2T1H (2 Mullibooms south of starting point. Use the sacrifice room above to damage yourself first)

PC PS4 Normal mode only JTMD EZPF (One mulliboom directly below the starting. Go left first to get weakened)

PC Hard mode only 4Z93 R21B (1 down 1 right from start contains mullibooms)

PC Hard mode only GH9Y FSA8 (series of rooms containing mullibooms going down)

PC Hard mode only Q2V4 YZET (Cellar needs to be unlocked, 2x2 room full of mullibooms (about 6/7) when going up)

Vita Normal mode only GQHN NMKN (Go left, 4+ Mullibooms)

3DS Normal mode only 6Z2L AZ6J (Go left, 4+ Mullibooms)

3DS Normal mode only VNSM AHHG (Go up, weaken yourself at the spikes, then go up and die from the Mulliboom)

3DS PXRT XH49 (Go up, weaken yourself with the Frowning Gapers, then go down and die to the Mulliboom)

iOS 3KY7 JPBJ (Go right and weaken yourself, then go left and there are 2 mullibooms)


PC ALFA 0NTS (Recommended Normal difficulty. Pyro in the first Treasure Room, adjacent to spawn)

PS4 FDRG 0CTE (Pyro in the first Treasure Room, adjacent to spawn)

Vita DXVW MQCF (Pyro in the first Treasure Room)

3DS YGDC T8SL (10 bombs in the first Treasure Room)

iOS E1NZ N3MA (bomb in second floor shop, the fires should give enough pennies to buy the bomb.)


PC Normal mode only YR8E YXDV (Polyphemus in the first Treasure Room. Do not take devil deals, as Trinity Shield and Sacred Heart will be available in Angel Rooms. Keep the Book of Belial to ensure they show up. Also, from the pills from Mom's Coin Purse (1st boss, Duke of Flies), take the orange (Health Up) then the white one (Full Health), ignore the blue ones (Speed Down)).

PC N0G3 VLD4 (Both modes) - Dr. Fetus on floor 1, and Ipecac on floor 2.

PS4 DMTM NRD9 (Do not make a Devil Room deal in Basement II will spawn an Angel Room with Holy Grail in Caves I. Collecting everything grant huge tears.

3DS 180Y 7RDC (Lots of health early (Rosary in first Treasure room), good pickups (Mulligan is in second Treasure room, Dr. Fetus and Mr. Mega in the third and fourth). Skip the first Devil deal, as the Angel deals are Sacred Heart, Mitre, and Scapular. Remember to trigger scapular before entering the Mom fight if you take it, as the immediate foot stomp may leave you with the bonus soul heart.)

iOS 0FP1 C9JK (The first boss room gives a heart, the first devil deal gives dead cat so you can survive.)


Using a seed on this step will not count towards unlocking The Lost.

The Lost

PC HNA6 WEK7 (Dead Cat and Holy Mantle on first floor, helpful for practice runs)

PC 616S GROG (Holy Mantle right of spawn, helpful for practice runs)

Unlockable Achievements[ | ]

Unlockable Starting Items[ | ]

Trivia[ | ]

  • The Lost's name and appearance hints that he is a ghost/soul/specter/spirit-type entity so lost it couldn't even find its way to the afterlife.
    • The name could also be linked to the fact that Isaac was presumed missing by his mother (as seen in Ending 14, and the fact The Lost is unlocked using Missing PosterMissing Poster), while in fact he was actually dead (as seen in Ending 17 and Ending 20).
  • When The Lost's unlock requirements were discovered through the use of data mining, Edmund McMillen and Tyrone Rodriguez both expressed their disappointment, considering it impatient and "like swallowing a hundred dollar steak in one bite".[2]
  • Right before the start of a run, some images appear to hint to unlocking The Lost, including the Missing PosterMissing Poster and The Lost itself.
  • (in Rebirth)Dying in a Sacrifice RoomSacrifice Room while holding the Missing PosterMissing Poster would yield a puzzle piece on Isaac's last will. These puzzle pieces, when put together, created the last wills of characters dying in the method used to unlock The Lost.
  • Before version 1.02, The Lost would die if a run was exited then continued.
  • When The Lost picks up an item, tarot card, or pill, you can see its arms that do not connect to its body.
  • Internally, The Lost has half a soul heart, which is hidden behind a permanent Curse of the Unknown-like effect. The singular soul heart is why The Lost can "pick up" soul hearts, black hearts, and eternal hearts. There are no ways to increase this health, though, as The Lost's health is constantly reset back to half a soul heart.
    • Devil deals appear as requiring three soul hearts each, as The Lost technically only has half of an invisible soul heart. This is cosmetic only, as devil deals are still free.
    • (in Repentance) The Lost can pick up soul hearts within the small timeframe of invincibility granted by Collectible Astral Projection iconAstral Projection after getting hit.
    • (in Repentance) The Lost can also do this while defying death using Collectible Berserk! iconBerserk!
    • (in Repentance) The Lost's health was visible on the HUD in V1.7.5 but was made invisible again in V1.7.6.
  • (except in Rebirth) A loading screen (when Isaac dreams) depicts the "Voice of God" telling Isaac's Mom to kill her son as The Lost speaking to her from the attic.
  • The Lost's starting health is listed as "?" on the character selection screen.
  • As a secret character, The Lost does not appear on the character select screen until unlocked.

Gallery[ | ]

References[ | ]