游魂#10

The Lost is a secret character. The Lost starts with no health and cannot gain health by any means. Therefore, he will die from any damage taken.

• The Lost starts with flight.
• 3DS The Lost also starts with D4 (if unlocked).
• The Lost starts with flight, spectral tears, D4 (If unlocked), and the effect of Holy Mantle (after donating 879 coins to the Greed Donation Machine)
• The Lost starts with flight, spectral tears, Eternal D6, and the effect of Holy Mantle (after donating 879 coins to the Greed Donation Machine). This form of Holy Mantle is inherent to the character rather than being a starting item, and as such will be present when switching to The Lost in the middle of the run through the use of Clicker, will not be present when switching away, and cannot be removed by any means. 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 Market items for free.
• 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 Room; only one of the devil deals spawned by the chests can be taken, regardless of how many chests have been opened.
• -0- Baby - Defeat Mom's Heart on Hard mode as The Lost.
• The Mind - Defeat Satan as The Lost.
• Isaac's Heart - Defeat Isaac as The Lost.
• The Soul - Defeat The Lamb as The Lost.
• The Body - Defeat ??? as The Lost.
• Zodiac - Defeat Ultra Greed as The Lost.
• Dad's Lost Coin - Defeat Ultra Greedier as The Lost.
• Sworn Protector - Defeat Hush as The Lost.
• White Baby - Defeat Mega Satan as The Lost.
• Holy Card - Defeat Delirium as The Lost.
• Lost Soul - Defeat Mother as The Lost.
• Hungry Soul - Defeat The Beast as The Lost.
• The Baleful - Use Red Key (etc.) to open the hidden closet in Home as The Lost.
• Godhead - Earn all 5 / 9 / 10 / 12 Completion Marks on Hard mode as The Lost.

• 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 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 Poster and The Lost itself.
• Dying in a Sacrifice Room while holding the Missing 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's heath is half a Soul Heart, which is hidden behind a permanent Curse of the Unknown-like effect. This is the reason why Soul Hearts, Black Hearts, and Eternal Hearts can be picked up. 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 with a ghost icon as their price to indicate that The Lost can take one for free.
• The Lost can pick up soul hearts within the small timeframe of invincibility granted by Astral Projection after getting hit.
• The Lost can also do this while defying death using Berserk!
• The Lost's health was visible on the HUD in V1.7.5 but was made invisible again in V1.7.6.
• One of Isaac's nightmares in the floor transition screen depicts God's voice telling 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.
• He shares this trait with ???, Keeper, and The Forgotten.
• The Lost is likely the manifestation of Isaac's worry, as seen in the final ending of the game. As the narrator says "His shame, his worry, pulled from his being," ??? and The Lost can be seen falling away from Isaac. This makes sense gameplay-wise, as The Lost is incredibly fragile, and intensive care (to the point of worry) must be put into making sure you do not die. Lore-wise, it also makes a decent bit of sense, but more so in gameplay.