The Basement Dweller's Guide to Spooky Ghosts (Or: How I Learned to Stop Worrying and Love The Lost) -- Updated for Afterbirth+

A comprehensive guide on how to unlock The Lost, how to unlock his associated achievements, and what items to look for and avoid while playing as him.

Background and Overview

Welcome to my guide for unlocking The Lost and his associated achievements. First off, I would like to point out that this guide will contain EGREGIOUS spoilers for endgame secrets and characters. This honestly should be common sense, but I want to point it out anyway. You have been warned.

If you're unfamiliar, The Lost is a hidden character in The Binding of Isaac: Rebirth. He is unlocked by dying 4 times as specific characters to specific enemies in a specific order, with no interruptions between deaths. This sequence was discovered by taking the Missing Poster or Mysterious Paper trinkets to a sacrifice room, and killing yourself on the spikes while holding them. Doing so would display a small image as the cause of death. This image is actually a puzzle piece, and when all of them are put together, it shows a series of game over screens showing Isaac dying to a Mulliboom in the Basement, Maggy to her own bombs in the Caves, Judas to Mom in the Depths, and Azazel to Satan in Sheol. In order to unlock The Lost, you must recreate this exact order of deaths.

The Lost has his own set of boss kill achievements, as well as the game's final secret. This guide will tell you how to unlock him, how the character works, and give some guidelines and tips for playing as him.

Important Information

Now before you get started, there's some things to note:

- - There is a much simpler method for unlocking The Lost if you own the Afterbirth or Afterbirth+ DLC. Skip steps one to four and look at step five, instead.

Dying in any way other than the steps specified, or doing those steps out of order, will not unlock The Lost. You must follow these steps exactly and in the order listed, or it will not work.

You can use seeds for the first three steps in the sequence. This makes it easier and much less time consuming. However, the final step must be done without the use of seeds.

Resetting in the middle of a run will not interrupt the sequence. If you are unhappy with the way your run is going, you can hold the R key to start it over without interrupting the process. If you're using a seed, you'll stay on that seed.

Do not pick up the following items or you will not unlock The Lost:
Lazarus' Rags()
Judas' Shadow ()
Ankh ()
If you die while holding these items, they will respawn you as another character. This will prevent you from being able to unlock the Lost, since you will not be dying as the required character (unless you happen to find Judas' Shadow on the Judas step).

Step One: Isaac

The first step is pretty easy if you're using a seed - all you have to do is be killed by a Mulliboom (pictured below and to the right) as Isaac while in either the Basement or the Cellar.

Seed: GPE3 2T1H

In this seed, the room directly north of the starting room is a sacrifice room. Enter it, and damage yourself to one heart. Then, enter the room to the south of spawn. It should be no challenge to be killed by one of the two mullibooms in this room.

If you decide not to use a seed, just keep resetting the first floor until you find some Mullibooms. It'll take a while, since they're not very common, but eventually you'll run across them.

After the Mulliboom kills you, go back to the main menu, and get ready for the next step.

Step Two: Maggy

Next up: bombing yourself to death as Maggy while in the Caves or Catacombs. This one's not super hard either, as long as you have a bomb at some point in the Caves.

Seed: 4PLT 46PH

This seed starts you with the Pyro item, which grants you an immediate 99 bombs. This should be more than enough to last you until the Caves. You can afford to use the bombs liberally, but be sure to save a few to use on yourself when the time comes. Otherwise, completing the Basement normally shouldn't be a major problem.

If you're not using seeds, just be sure to have at least one bomb on hand by the end of the caves. Throw yourself into an enemy until you're at one HP, then drop a bomb to finish yourself off. I doubt the game would be so evil as to not give you a single bomb for four levels, but I guess anything is possible with Ed's patent-pending TrollEngine™.

Once you've blown yourself up, continue to the next step.

Step Three: Judas

Now we're getting to the slightly harder parts. Step three requires you to die as Judas during the Mom fight in the Depths/Necropolis II fight.

Note: You have to die specifically to Mom, not the enemies she spawns! This includes the stomp attack, the eyes/lumps of flesh that poke out of the doorways sometimes, the fist attack, and the projectiles fired by the Red champion version of Mom.

Seed: YR8E YXDV

The first item room contains Polyphemus, which will make your damage output phenomenal. If you don't take any deals with the devil, you'll also come across the Trinity Shield and Sacred Heart in item rooms. Make sure to keep the Book of Belial to ensure that devil rooms always spawn. If this seed doesn't work for you, really any seed that guarantees you a powerful run will work.

If you're not using seeds, this one could be a bit challenging, since Judas can only tank two hits to begin with. Focus on dodging, and just play it like any other run.

Now get ready for the final stretch, because there's only one more step until you unlock The Lost.

Step Four: Azazel

Do you smell that? It's the sweet smell of victory, and the source of the aroma is not far away.

The final step in the process involves playing as Azazel. You'll have to take him all the way to Sheol and have him lose to Satan. The fight with The Fallen before Satan spawns will not count, nor will the black leeches that Satan spawns. You must die to either Satan's first form, or to the stomps in his second form. Anything else will reset the sequence, and you'll have to start it all over again.

Bad news - you can't use seeds on this step. This means that you have to actually play legitimately. But it's not all bad, considering how powerful Azazel is. It shouldn't be a major challenge to reach the Satan fight as him.

However, if you're dedicated to cheesing the achievement, you can always reset until the first item room has something insanely powerful in it, like Ludovico Technique or Mom's Knife. If things start looking rough, restart the run and try again.

Also worth nothing is that when Satan reaches his second form (where he stomps on you and summons leeches) he will be damaging you exclusively with explosive damage. If you have the Pyromaniac item, which heals you when you are hit by an explosion, make sure to be killed by Satan's first form, or you won't be able to die to him at all.

After Satan kills you, you should get the popup confirming your achievement. Yay! If you didn't get the achievement, reread the guide to make sure you did everything correctly. If you're positive you did it right, then make sure to yell at me and tell me how terrible and stupid I am. I'll go back and try to correct whatever mistakes I might have made, and then flog myself thoroughly.

Step Five: Unlocking The Lost with Afterbirth installed

The advent of the Afterbirth DLC made unlocking the lost significantly easier. All you have to do is die in a sacrifice room while holding the Missing Poster trinket. (This was method used to discover the sequence of deaths needed to unlock The Lost originally; dying in this way would display a puzzle piece on the death screen, and completing the puzzle would show you how to unlock The Lost.) Keep an eye out for it, as well as the Mom's Box item which spawns trinkets on use.

Boy, that was much easier, huh?

The Lost's Attributes and Stats

You did it! Pat yourself on the back, because you have successfully unlocked The Lost. Certainly, a character with such an arduous unlock process should be incredibly powerful, so let's kick back and breeze through a few runs as the most overpowered character in the ga-- nah, just f*cking with you.

The Lost is unique in that he starts with no heart containers at all. Health up items do not add more of them. You can't even pick up soul hearts. When you're playing as The Lost, being hit even once will immediately kill you.

Naturally, a character with zero hitpoints cannot make good use of any item that affects his health, or requires you to hurt yourself to use. Many items you encounter will be useless. You can't use curse rooms reliably and you can't use sacrifice rooms at all.

However, The Lost also has some positive attributes. For one, he starts with the ability to fly, which is rather useful. While he doesn't have spectral tears, meaning you can't attack while on top of rocks, you can still escape from danger much more easily. Also, since The Lost has no health to trade, all devil room items will be free (and since you can't take any damage anyway, you'll be encountering a lot of them).

Other than his health, The Lost's stats are identical to Isaac's:


The Lost starts with one coin.

In the Afterbirth DLC, The Lost received a considerable buff. He will have spectral tears from the start, allowing him to shoot through rocks. This compliments his innate flight very well. Additionally, he starts with the D4 (assuming you have unlocked it at all), allowing him to reroll all his current items on use. Finally, by donating a whopping 879 coins to the Greed donation machine in Greed Mode, The Lost will start with the Holy Mantle. With all of these changes, playing as The Lost is significantly easier.

Achievement Guide and Unlocking the Godhead

Like every other character, The Lost has a set of unlockable items associated with him. Godhead is unlocked slightly differently if you have the DLC installed.

(Sorry about the wonky floating tags, I have no idea how to get rid of them.)

Item	Effect	Image	How to unlock
The Mind	Permanent full map (combined effects of Map, Compass, and Blue Map)		Beat Satan
The Soul	Causes projectiles and flying enemies to be pushed away from Isaac if they come near to him, also adds 2 soul hearts		Beat The Lamb
Isaac's Heart	Makes Isaac himself completely invincible, but gives him a floating heart familiar which will take damage in his place		Beat Isaac
The Body	Adds three heart containers, and heals Isaac for three hearts of damage		Beat ???
D100	Combined effects of the D4, D6, and D20 - rerolls all of Isaac's current held items, all pedestal items in the room, and all pickups in the room; 6-room recharge time		Beat the Boss Rush room
-0- Baby	Playable co-op baby; completely immune to contact and projectile damage		Beat Mom's Heart on hard mode
Godhead	Gives you homing shots that have a damaging halo around them; increases your damage and range, but lowers your shot speed and rate of fire		Beat Mom's Heart, Satan, The Lamb, Isaac, and ??? on hard difficulty
The next four rows relate to content from the Afterbirth DLC.	Zodiac Each floor, Isaac is given the effects of one of the twelve zodiac-themed items for the current floor Clear Greed Mode	Sworn Protector Orbital familiar; blocks bullets, attracts enemies, and does damage on contact; may drop eternal hearts when blocking bullets Beat Hush	White Baby Playable co-op baby; grants Isaac an eternal heart when spawning [/td] Beat Mega Satan [/tr] Godhead Gives you homing shots that have a damaging halo around them; increases your damage and range, but lowers your shot speed and rate of fire Beat Mom's Heart, Satan, The Lamb, Isaac, ???, Hush, and Mega Satan on hard difficulty. Clear Greed Mode The next two rows relate to content from the Afterbirth+ DLC. Holy Card Card slot pickup; gives you the effect of the Holy Mantle for one room, effectively blocking your next hit of damage Beat Delirium Dad's Lost Coin Range up; spawns a penny that increases your luck stat when you pick it up Clear Greedier Mode

Notable item synergies

Since The Lost is such a challenging character to play as, here is a partial list of items that compliment his unique attributes well, as well as a partial list of items to avoid.

Good items

• The Dead Cat is incredibly useful, since the caveat of respawning with one heart container doesn't affect The Lost at all.
  
• Any item that offers protection, such as the Holy Mantle, Infamy, Trinity Shield, Lost Contact, and any orbital (Halo of Flies, Cube of Meat, etc.) are invaluable.
  
• Items that give you spectral tears allow you to take better advantage of The Lost's flight.
  
• The Wh0re (thanks, steam censoring) of Babylon is always active, granting you significantly boosted speed and damage.

Bad items

• Items like Leo that allow you to crush rocks by running over them remove one of the Lost's only advantages: using objects as cover.
  
• Items like the Sharp Plug and Blood rights will kill you if you use them.
  
• Items that grant flight are obviously redundant.
  
• Items that add explosive effects to The Lost's tears, such as Ipecac or the Fetus in a Jar, should be used with caution, as one errant shot could end your run.
  
• Ironically, the D4 that The Lost starts with should be used with caution, as it will reroll your Holy Mantle.

Credits, Thanks, Etc.

Misc. info, seeds, and images: The Binding of Isaac Rebirth Wiki at Gamepedia[bindingofisaacrebirth.gamepedia.com]

Guide icon: "Isaac and the Gang" by Not Your Sagittarius

Thanks to Edmund, Nicalis, and Ridiculon for a fantastic game!




--

(Please don't add me as a friend on Steam. If you have a question, ask in the comments, but I'm not looking for random friend requests. Thank you.)

[PolientTheGuy]

uwu

[Spyshark]

That moment when all Afterbirth buffs translate to Antibirth

*Witness's theme starts playing*

And since that The Lost is my MAIN, this guide was more as a helpful tip or two. Good guide though!

[Serious Scully]

It kinda sucks that the lost is practically impossible to play until you donate 879 coins to get the holy mantle. The best thing was that the moment I did unlock it, I beat boss rush, isaac, it lives, satan, and also killed ultra greed.

[cosmobird]

@BeansOnToast srsly you CANT use a seed for azazel

[Rhombicosidodecahedron]

m8 get a seed for azazel

[Degiomo]

Elephant on a unicycle: how many times die i have to die in the sacrifice room

[Ele]

7atamgames: No, the original sequence of deaths doesn't work in Afterbirth; I have edited the guide with relevant information in that regard. See step five.

[Degiomo]

is it work in afterbirth

[wow]

Good guide if you want to unlock the Lost, but not actually a guide on how to beat/use him

[fish]

Working seed for Isaac: J3QJ Y7XL
Mullibooms are on the first room to the south of the starting point.