Chapters

==The Sewer==
By unknown
(Sewer 1, Sewer 2)  As soon as I heard that WOTL was coming out and alternate floors were announced, I thought that a Sewer floor would make a great caves replacement.  I thought of this a LONG time ago, and i'm sorry if someone else wrote this already, I haven't read every single post on this Wiki.
Alternate floors to Caves.  Unlocked by fighting every Super Sin (Or just unlocked after a set amount of playthroughs)
A green, nasty, infested sewer full of poison and death.  The walls are stained green and pipes and the odd bit of plant life line the walls.  The floor varies between metal, cement, and nasty water (all of which are purely visual).  Darker water is like Pits, you cannot walk over it.
Some rooms would be resembling a Sewer version of the Catacombs and most other would be completely sewer-like.  The Sewer rooms could have odd dimensions to them like having some rooms be very long and Sewer-esque.  Instead of a door, some rooms would just have open walls so it seems like one room even though it's two.
Instead of Spikes, there is Sludge (which hurts you if you stand on it for too long.)  Which would be like water streams and would not usually be just a singular Sludge block.  There are Spider Webs and Poop Piles as well as Pipes (which would be like rocks, except require a bomb and a few tears to destroy.
Full of a few new enemies like Rats, Snakes, and Bats, as well as Spiders and Flies of course.  
About as hard as the Depths is but not as hard as Necropolis.
One boss would be Servantes (a Serpent that spits poison and spawns Guts, Gurgles, and Poison bombs as well as moving around the Boss Room in quick intervals.
Another could be Alukard (for lack of a better name) and giant bat that spawns bats and flies over you and swoops down.  When he flies over he doesn't have a hitbox but when he swoops down he does.
Instead of a Trap Door, you find a Manhole after defeating a Boss.
The Needle items would be slightly more common as well as any poison themed items.  
The Secret Room is a mini-boss fight every time where you face either Super Sloth and Sloth or two Peeps (which are tinted green and release poison instead of pee.)  The prize is The Common Cold or Spider's Bite or any Poison-themed item as well as one random Needle.
== Charnel House ==
Charnel House is a floor unlocked after beating Necropolis 1 or 2 35 times. When you get to Charnel House 3, it will instead appear as Charnel House 666.
=== Enemies ===
Skeletons, Fossils, Skulls, Boneheads, spiders, and bats.
=== Charnel House I Bosses ===
Ebony
Alzheimer
Hearse
=== Charnel House II Bosses ===
Cholera
Eighty, H, & Dee
Death
=== Charnel House III Boss ===
At the boss of Charnel House III, the boss will always be 1 single boss.
Mortem Health-6666 ( Same health as Hush)
After beating Mortem, 2 chests and 1 trapdoor will appear. 1 of the chests lets the player beat the game. The other chest leads the player to the floor Chest. The trapdoor leads the player to Dark Room.
==Sin World==
By unknown
Unlocked by beating Sheol with The Book Of Sins. After beating Satan, a trapdoor will appear and you will teleport into Sin World (don't need the Book of Sin).
Every room you'll encounter 2 Sins or 1 Super Sin
The boss is all Sins, Super sin and Ultra Sins.
After beating the bosses you will unlock sin injection
If you beat with book of sin you will unlock the my lovely sin familiar
The sin injection is a activable item when you active you tranform the enemies in pick ups, 6 rooms to recharge
My Lovely Sin is a familiar, he acts every floor with a random sin, the power of spawn dont act Ex : in cellar he acts the greed, shoot projectiles when hit the enemy drop coins.
==Dad's Office==
By unknown
Unlocked by beating The Chest without taking damage.
In the rooms of Dads Office you will encounter all champion enemies and the Seven Super Sins.
The boss is your Dad. After beating Dad you will unlock the Dad's Head Familiar.
If you beat him without taking damage you will unlock Dads Wallet, and the D50
Dad's Head will shoot Brimstone but has a 4 second charge. He has a 1 out of 30 chance of being in the treasure room and a 1 out of 50 chance of being in the shop for 20 cents
Dad's Wallet is a Trinket which drops a Dime every stage Ex: You beat Basement 1 with Dads Wallet and when your in the celler (or whatever) you will earn a Dime
The D50 Will reroll Bosses and enemies. Its a spacebar item and it takes a 6 room recharge
There is a Shop in Dads Office but the Shop's Prices are doubled. So a red heart is 10 cents unless you have steam sale which will keep the prices normal.
==The Rodeo==
By unknown
Unlocked by defeating every horsemen across all playthroughs. After beating Mom you will get the choice of going to the Rodeo instead of the Womb via a lasso. In the rooms of the Rodeo you can encounter the seven deadly sins and the seven super sins along with mini-boss versions of bosses in the basement and caves. All floors in the Rodeo have a horsemen as a boss. Unlike the Womb or Utero the Rodeo has treasure rooms and shops but The Rodeo 1 has the treasure room while the Rodeo 2 has the Shop.
==Limbo==
By unknown
Unlocked by finding a Limbo Room in the Womb II.
After going down the trapdoor in a womb II limbo room limbo is permenently unlocked. All the enemies here are bosses. 
Limbo has about 60 rooms in it so this is @#!*% . Limbo comes in both 1 and 2.
In Limbo 1, a room can consist of:
*4 Greed
*2 Super Greeds and Peep
*8 Larry Jr.'s and Super Wrath
*4 Envy
*5 Pride
*3 Lust 2 Super Lust
*8 Sloths + 1 Super Sloth
*4 Fistula + 3 Vomit Grimaces
*First boss is either Destruction or Catalyst (see: bosses)
Limbo 2 on the other hand is a huge 30 x 30 chunk of rooms with no enemies. To get to the boss room you have to see how many fireplaces are in each room. In the begining area there will be a fire pointing to the direction where the boss is. So you baically have to play hot/cold with the game until you find the boss.The boss is called Arson.
Trust me, it's a LOOOOOOONNNNG and tough fight.
==The Attic==
By unknown
Entered by using "We need to go Deeper" in The Chest.
The Attic is a room that appears to be the Cellar, but Littered with Spiderwebs even moreso then usual, and the place is much darker. Isaac's Tear Rate, Damage, Speed, and Health are set to 1. The room generation is that of The Womb XL, and the Only Monsters that appear are Spiders. Red Chest's spawn often. It has no music. The Boss room is indistinguishable from any normal room, and that is further shown by the fact that the room can have Multiple entrances around it. There is no indication that it's a boss room once entered, either. In the center of the room is a lone Red Chest, surrounded by Spider Webs. Once opened, you can hear a low stomping in the Background. After 5 Seconds, all doors in the Room Lock, and a completely Normal Daddy Long Legs Boss-Fight begins. The Spider Web's effectiveness temporarily increases to slow you down long enough to prevent you from leaving before the doors slam (and there's an invisible wall at the edges of the spider-webs for the duration aswell). After the fight, Daddy Long Legs groans, and does one final Head Slam attack, demolishing the Floor, and sending you to your Death.
Comment: So what happens then?
==Time Machine==
By unknown
Unlocked by beating sheol or the cathedral, or by seeing every boss up to the womb 2.
Got to by beating a boss with both technologies, or by beating mom's heart/mom/it lives/satan/issac/??? with technology 2.
Has a 50% chance of appearing on at least your 40th playthrough. any time before that is 1%.
A grey area with lots of wires all over the place. no rocks or poop, and fires are very rare. fire will create more fire on every adjacent sqaure every 3 seconds. when fire is destroyed it leaves behind a scorched area that damages for half a heart every two seconds. it lasts until you leave the room.
Each room will have enemies from a different area. for example, If an enemy only appears in the womb, It will not be seen with a basement 2 enemy. The boss can be any boss up to where you found it. If you beat It lives, than It can be any boss up to that point, including mom, mom's heart, or it lives.If you got there after beating satan, issac or ??? will not appear as a boss on that playthrough.
Has a 30% chance to lead to the basement, a 25% chance to lead to the caves, 20% chance to lead to the depths, 15% the womb, 5% shoel/cathedral, and 5% the chest.
You keep your items upon going back.
==House==
By m.m79
If you jump a floor upper than basement (with mymade item kaangaaroo!! ) you will see isaac`s house.there isn`t any enemy ,rock ,fire or poop..place what shows your pickups disappears and isaac won`t shed tears any more.map is revealed cause isaac knows his home .treasure room is the kitchen (or mom `s room)and has all mom`s items(or only her knife).boss room is isaac`s room that can be known from the crack on it . the boss is true mom.after killing her you will have a trapdoor to the basement and stairs to the rooftop.
==Rooftop==
By unknown
Rooftop is a floor with only a Boss room.The Boss is daddy (?).
==Space==
By tracotaper
If you get to i am error room or bring the poloroid in sheol you will end up in space</p>
in space all alt boss are fought here and all sins 6 normal 1 super with (3 in room)
all enemys are champions you have bomb turrets. pyscic maws spike traps and other unholy things
the starting room has spikes around it and it looks like the night sky
the boss is kaos who looks like a pair of red eyes in 1st form
once space is beaten you get isac: isaacs undies cain:cains other eye maggy:maggys heart judas:judas lips blue baby:???s life eve:eves freind sampson: sampsons hair tonic noah:noahs plank
all items are passives
==DOOM (Lucifer's Floor \ Sheol II)==
By Qw3rtypounc3s
The entrence to DOOM can be found after beating ??? in the Chest.
The floor's rooms are gathered in a straight line (Besides the first room and the Boss room, the doors in the other rooms are always parallel). The floor only contains Bosses and mini bosses. The Boss in DOOM is always Lucifer. DOOM can be acessed early if you go into a secret room and notice a devil room door, then the room on the other side of the door leads to the passage down to DOOM.
Enemies in rooms:
*2 Bloats
*4 Different sins
*3 Different Super Sins
*3 Wretcheds
*5 Lokis
*5 Widows
*3 Gurdy Jrs
*1 Gurdy
*3 Chubs
*3 Carrion Queens
*3 Monstro 2s
*3 Peeps
*2 Daddy Long Legs
==Purgatory==
By FlashMasterXD
The entrence to Purgatory is the opposite to the ??? floor. After beating Satan 5 times, in the 5th time a beam of light will appear in the middle of the room. It will lead the player to Purgatory, witch always has 10 rooms. It mostly has the same enemies as Sheol and The Cathedral. The Boss in Purgatory is always Demon Isaac.
==The Chest==
By Njpucillo
After fighting Isaac (or ???) a gold chest will spawn and touching wont give you the ending but put you into the new floor "the chest". This floor is the size of a tipical Caves II and is darker than most floors. Each room will have a boss (normal boss or seven deadly sin) The boss of this floor would be Daddy Long Legs unless you have my reflection, if you have my reflection (or 3 dollar bill) you will fight Cassi. The Alt. Chest would be The Cage which is the same but is the size of the Womb I and has Super Sins. If you have my reflection (or 3 dollar bill) on The Cage the boss will be Demon Isaac, if not you'll fight Triachnid. (Note: this was written before update 1.3)
==The Graveyard==
By Blueplastic
Constantly spawns enemies without stopping.
Has 3 types of gravestones across the room:
*cracked gravestone - can be destroyed with normal attacks
*solid gravestone - can be destroyed with explosive
*skulled gravestone - you have to kill certain number of enemies without leaving the room
They drop items, chests, enemies, grim reaper (mini boss like Krampus)
==Home==
By Powerpal52
Isaac's home, is unlocked after completing the whole game. No monsters and no Mom. You can do activities there, such as, Explore items, Draw, Kitchen and other stuff that im going to have to think about. You can access it by the main menu. Plus, you can also access it before you complete the game, only that you can PLAY the intro like running away from mom and going into the basement.
==Destroyed Chapel==
By Spartz117
After beating Cathedral, you will rarely find a hole, going out will do the Sheoul music when you buy something, the music will be people singing the hyms, the place lookes like the cathedral, but broken, like the enemies from Sheol come, Librarians pretty count as regular monsters in this place, mini fetuses are not rare in this, and the last boss is Satan 2 (found at the boss section) the 13th ending is just all the other endings but rewinding really fast, as if Isaac was going back to the past, then unlocking an item called the broken bible, which sends you back to the start, but with you still with your items. Andrew can skip Cathedral and get to the chapel.
==The Library==
By Spartz117
The Library is a place that is an alt. of Cathedral, it sometimes replaces Cathedral.
Enemies:
*Mr. Maw
*Mini fetus
*Mimic Maw
*Librarian
*Pacer
Bosses:
*Priest
*Satan 2
*Hostile
Last boss: Dr. Fetus
==The Brain Chamber==
By unknown
Occasionally replaces the Womb or the Utero. Unlocked by beating it lives without taking damage. Gluttony is always fought before the boss room.
Enemies:
*Host
*Baby
*Gaper
*Mr.Maw
*Knight
*Gluttony
Bosses:
*Steven
*C.H.A.D
*Gish
*Lokii
*Terratoma
Final boss: Mom's Soul
==The Void==
By unknown
There will be a rare chance that occurs after beating Isaac (boss) 5 times that after defeating him a hole will appear (One that goes to another floor). You have the option of the hole or the chest. If you choose the hole, you will go to The Void. It looks dark-blue with cracks everywhere and has track 38 (Tomes).
Enemies:
*Super Pride
*(Champion) Dark Blue Psychic Maw (Does more damage)
*Super Envy (With a darker tint)
*(Champion) 4 Blue Larry Jr.
*(Champion) 2 Blue Chub
*(Champion) 3 Blue Duke of Flies
The boss of this area isn't a boss at all, but a mirror. You are trapped in the room with the mirror, and all you can do is attack it, which slowly cracks the mirror and drains your health.
After you die, a new ending is unlocked where the mirror becomes a swirling vortex and sucks Isaac in. He then is swirling throughout time and space, trapped, with nothing to do.
==The Holy Land==
By Njpucillo
The Holy Land is a floor which is very hard to access. You must fight ??? in the chest (the real ingame one not the one i made up) you must have the bible, the polaroid, mom's purse, and any of the 7 characters body parts trinkets. When you defeat ??? and the chest shows up you need to use the bible and you'll be sent to the holy land. At the start there will be 2 random angle room items. and bordering the room is one other room, and boss room where you'll fight any basement/cellar boss. After you defat that boss you wont get a boss room item only hearts, bombs, pills, etc. Bordering that other boss room is another boss room where you'll fight a random caves/catacombs boss. Bordering that room (there is a pattern here btw) is a boss room where you'll fight a random depths/necropolis boss (not including mom). Bordering that room is another room with 2 items but this time 2 devil room items (fo FREE) Borderong that room is yet another boss room where you'll fight a random womb/utero boss (not including mom's heart/it lives). And next to THAT room is another boss room (tired of this yet? Well just inmagine playing this) where you'll fight Satan. and after fighting him you'll go thorugh another boss door that takes you to the final boss (finally!) the final boss is "The Holy One" which is just isaac's final form with the HP of a normal boss. After killing him the end chest will appear and touching it will give you the 13th ending. BUT there is also secerts/achievements for beating it with different characters! Isaac=Left Foot, Maggie=The Heart, Cain=Left Eye, Judas=Right Foot, Eve=The Torso, Samson=The Mustache, and ???=The Head. I'm not sure about those yet since imuncreative but they'd all be trinkets (and if you haven't noticed they make up a person....BUT WHO OOOOOOHHHHHH) So that's all i got for now!
==Isaac's Madness==
By Lazerguy555
A floor which takes place of The Chest when Isaac (Boss), Satan, and ??? (Boss) are defeated at least 5 times each. The walls are black and purple (purple on the edges) The edges of the walls waver back and forth, and the rocks are black (trimed with purple too) and doors look open when they are closed and vice versa. The monsters encountered are: Monstro 3 (Like Monstro 2 except has the same effect as Fistula) Larry (REALLY long Larry Jr.) and Master (a horsemen who throws super troll bombs at you and summons 8 troll bombs at you) The Isaac's Madness floor only has 6 rooms. 3 are random, the starting room, and a item room that always contains the item I made "The Corruption" (The item's info is in the user Item Ideas list) The final room is the Boss Room, containing the final boss, Madness. Madness Is a giant eye that shoots Technology lazers out of it, which are super fast and deal 2 hearts of damage. When you touch him, you get slowed. When he rams you, you get confused and your con trols are switched. (Left=Right and Right=Left, Up=Down and Down=Up) When you defeat it, it enters its second phase. He turns into a giant hand. He'll be able to fly, so it can pass through rocks. His first move turns him into a fist and he pounds on the ground, dealing 3 hearts, also destroying rocks. his second attack makes him swipe at you with his hand, dealing 2 1/2 hearts if the player is hit. His 3rd attack summons 2 Monstros OR 2 Gurdy Jrs. OR 2 larry Jrs. OR 2 Mini Fistulas. His 4th attack turns all remaining rocks into knights. When you kill him, there is a white flash and the last ending rolls. It show Isaac waking up from inside a mental hospital.
==The New Genesis Stages==
By Mnemonical
A set of new stages; effectively an alternate "campaign". For info on the new enemy types and bosses, see my submissions in Fan Ideas/Enemies and Fan Ideas/Bosses.
===The Boiler Room===
Two sets of floors with a steam-punky motif to them, serving as the first floors of this new scenario. You'll find generic enemies from the Cellar and Basement in here, mostly Clots, Trites and Spiders. Bosses that can be found on these floors are: Monstro, Widow, Gurdy.Jr, Famine, The Fallen and Headless Horseman. Rusted tiles can be found in rooms. These will hurt you for half a heart when walked over, but do not hurt enemies.
===The Subterra===
The next two set of floors, set in a dark-ish underground tunnel system, like the Caves but a lot more gritty and with patches of vegetation in places. Enemies from Catacombs and Caves can be found here, with a focus on Blockages, Super Pooters and Hosts. Leeches can be found rarely as well. Bosses fought in these floors range from: The Husk, Chub, Blighted Ovum, Pestilence, The Fallen and Headless Horseman. Shrubs can be found throughout the Subterra; these can be destroyed with a chance of dropping hearts. If the player has the Candle, they can light the shrubs, effectively turning them into fires. New enemies include Vomit Pooters.
===The Crypt===
These floors follow a much more stoney theme, with various bones across scattered across the floor and gothic aspects in scenery. Enemies from the Depths and Necropolis can be found within, but most enemies found will range between Globins, Knights and Swarmheads. Turrets are also common here. Bosses found down here can be: Scleteris, Mask of Infamy, The Bloat, War, The Fallen and Headless Horseman. Brittle rocks can be found in the Crypt; they can be destroyed with a few tear shots. These rocks cannot drop items, but can make bridges across gaps. New enemies include Boneheads and Pilferers.
===The Mausoleum===
A darker grey set of floors with a more polished texture to them, but random spats of blood and other fluids in places too. Enemies from the Necropolis can be found here, and certain ones from the Utero and Womb, including Leeches, Eyes and Knights. The Seven Sins can appear as room mobs, as well as versions of Larry Jr., Monstro and Pin. Bosses found within these parts include: Lokii, Triachnid, any one of the 7 Demons of Sin, Death, The Fallen or the Headless Horseman. Spike trap tiles can be found throughout the Mausoleum. These occasionally raise up spikes that hurt for one heart of damage. Players take one heart of damage throughout these levels. New enemies include Boneheads and Marrows.
==The Shadows==
By Pillbox15
After beating ???, you can then proceed to "The Shadows" which is basically a much longer, and much harder version of The Chest. If you got another trinket in The chest, DONT swap out The Polaroid or you wont be able to get to this area!!
In the first room there will be 2 random trinkets, 4 red chests that usually contain soul hearts or very rarely a super troll bomb, and 2 golden chests which both contain items. The rest of the floor is going to be a nightmare!
Curse of Darkness always will happen on this floor unless luck is very high, playing as Cain or if you have been lucky enough to get 2 Angel Rooms in the same run. The soundtrack for this floor would most likely be the new boss fight music in the DLC.
Which Bosses are capable of appearing in 1 room:
*4 Larry Jr + 1 Gurdy Jr *Or 5 Larry Jr, all up to 4 segments long*
*4 Monstros *Most likely black champion Monstro*
*4 Duke of flies *Often the green champions*
*3 Gemini *Sometimes 4*
*Any 3 Harbringers *Conquest or Headless Horseman also possible here, or 4 Horseman Heads*
*4 Widows
*3 Wretched
*Scolex + 2 Pin *or 2 Scolex*
*3 Gurdy Jr *If facing the small blue champions, up to 5 can appear*
*Gurdy and 2 random sins *Usually Greed, but sometimes can be other sins*
*3 Blighted Ovums
*3 Husks
*3 Hollows *Champions likely*
*2 Peeps *Sometimes 3*
*Chub and 2 Carrion Queens
*3 Monstro II *Not aligned so the laser trick wont work*
*4 Loki or 3 Lokii
*2 Daddy Long Legs
*2 Masks of Infamy
*2 Bloats
*2 Fistula or Teratoma *Or one of each*
*2 Blastocyst *Full size*
*2 Fallens
*Krampus
*5 or 6 random deadly sins *possible to get the same sin more than once*
*3 random super sins *possible to get the same sin more than once*
*4 super sins of the same type
Normal enemies that can appear on this floor:
*7 Angels
*8 Leeches *4 of which can be explosive*
*Several Spiders or Knights *or a combination of both*
*5 I.Blobs
*6 Membrains/MamaGuts
Other Rooms:
*Room full of red poop *you gotta shoot a path out, there will be chests in here to lure you*
*Room full of Rocks *bombs away!* pretty much an empty room if you can fly. you cannot run into this room if you don't have enough bombs to complete it.
When you have made it to the boss room, you will then have to fight Isaac, followed by Satan, Followed by ??? *basically as a mob trap room*. Then, another room will open and the TRUE final boss will appear...
Since youve made it this far, pray for a quick death.. or god help you.
There is no ending for this floor. This is just a challenge for those few brave enough to enter. *If you dont want to do this area, a random trinket will appear after ??? is defeated, pick it up and walk into the chest to end the game as normal*
==Blind Faith==
By moosie666
Entrance is trapdoor with black light coming out
1 floor with curse of darkness (half the size of cathedral/sheol for fairness)
can replace cathedral/sheol
boss:isaac (ending is still ending 13)
==The Sewer==
By Houston691
It is unlocked by completing The Basement/The Cellar 1&2 50 times
After completing The Basement/The Cellar, you will go to the Sewer.
It always has 5 rooms in a horizontal line.
There are no secret rooms.
If you get Curse of the Labyrinth on it, it is double rooms.
Only bosses spawn in rooms.
The treasure room has 2 angel room items.
That is the first room. The left "Grate" is the treasure room.</p>
The item in the middle is the Snorkel Mask, which allows you to swim through water.
There is a chance it will be the Water Shoes, which allow you to walk over water.
Added by Houston691
This is a normal room. The bosses in it can walk over the water.
Bosses/Minibosses in rooms:
*2 Monstros
*3 Larry Jrs.
*2 Widows
*2 Pins
*Famine or Pestilence
*1 Gurdy
*2 Different Sins
*1 Super Sin
*1 Chub
==The Chestception/Chest 2==
By Houston691
Unlocked by completing The Chest 10 times.
The start room has 10 wooden chests all containing items
(This floor is insane...)
Rooms:
*4-6 Monstros
*5-7 Widows
*3 Different Horsemen
*4 same Horsemen
*3 Ultra Prides
*All 7 Sins
*5 Super Sins
*4 Wretcheds
*4 Gurdy Jrs.
*3 Scolexes
*2 Triachnids
*2 Bloats
*Gurdy
*4 Peeps
( and if you're VERY unlucky: )
*10 Harbingers(10 death O_O)
*12 Monstros(wow...)
*14 Widows(how the @#!*% does that fit in a room?)
*13 Sins
*3 Triachnid(stomp stomp stomp!)
*4 Bloats(JEEZUS)
*5 Fallens (10 mini fallens? usrs?)
*3 Mask of Infamys
*10 Gurdy Jrs.(...)
( those rooms have a 0.02% chance of spawning)
==The Meadow==
By Fox0427
Unlocked by exploring the entire floor of "The Chest" and beating "???" within 15 seconds of entering the boss room. Entered by completing "The Chest".
The entire floor has NO walls except the edges of the map which are hedge maze bushes, the floor is "The Chest" with "Curse of the Labyrinth" except with four floors on top of each other instead of two.
The boss of "The Meadow" is "Isaac's Sins" which is the demon looking Isaac that he sees in the mirror of "End 12" and has 3X as much health as ??? and has the almost same forms (laying on the ground, standing up except this time he looks mad and there isn't light around him, and wings, except no light around him and he has demon wings). The first form shoots blood tears instead of normal tears, doing 1 1/2 hearts, when shooting homing tears he shoots 8 out. The second form shoots 12 homing tears (only difference for second form, he still shoots blood tears), and the final form shoots 20 homing shots at a time and spawns "Demon Baby's" (see enemies, not added by me into enemies but I liked the looks of them), Bomb Leeches, and The Fallen.
Each room contain 4 random bosses, but since the walls are open, you can easily skip each room and only have to fight the ones right before the boss room, but completing a room has a 25% chance to get a random item.
==The Spectrum==
By TheDarkSheep
After Defeating ??? for the 5th time, You will Unlock A Dark Portal which leads to 'The Spectrum'. Warning: Must Have the Polaroid Trinket Upon Completing The Chest
In the First Room, There will have 4 Red Chests,3 of the Red Chests Contain 2-3 Spiders while one of them contains Random Items' (Rarely Epic Fetus and Brimstone). 'Once you leave the first room, it will be a hardcore...
There would only have a 20% chance that the Whole Floor would be Normal and Not Having The Curse of Darkness, The Soudtrack of Every Boss (and Miniboss) is My Innermost Apocalypse, Which is ???'s Bossbattle Soundtrack
Upon Leaving your First room, You will find yourself in a Mini boss fight (Larry Jr.,Monstro 2,The Husk,Lokii,or Daddy Long legs) in EVERY Direction of whitch you desire to enter upon leaving the First Room.after Leaving the Second Room, there would be a 50% Chance that you would encounter another Mini Boss (4 types of the Seven Deadly Sins), and the rest of the Rooms are normal ones (Unless you went to a second or third room near the First Room)
The Final Boss Would Be Brimstone Isaac Himself (or Demon Isaac to be Specific)
Ist Form: With the same attacks as Boss Isaac
Second Form: Stands up then Attacks with a Blood Beam Similar to the Brimstone Charge Attack,can also attack with homing tears
Third Form: Flies with his Demon Wings, Health increases every 30 seconds, and attacks like The Fallen
==Cotton Alley==
By Njpucillo
The Cotton Alley is a floor that can appear as a replacement for any floor but very very rarely, you can increse the chance of finding the floor by having more Super Meat Boy related items. The music played on this floor is the Cotton Alley theme from SMB. This floor is very bright and pink (like that brightness glitch) It is the size of the Depths 1 and has every room the Chest has (the real one not the one i made) But unlike the chest there is no free items, no shops, no item rooms or curse rooms (But high chance to find trinkets). The boss is Dr. Fetus and when defeated gives you Fetus in a jar or Epic Fetus (50,50). Once you leave the floor you continue the game normally.</p>
==Omega==
By DarkDXZ
Omega is a bonus floor, unlocked by beating Satan while holding the Polaroid (which is required to enter it on all subsequent runs, similar to the Chest). Omega's design is similar to the chest, but looking much more like the Red Chest, as opposed to the Golden Chest (red frames, black/burned wood). Omega chapter theme is "Thine Wrath..." (Mom's theme) In the spawn room, there are always 3 Red Chests, each containing a devil item. No drops spawn on the floor aside from them, though. (with exception of Red Chest rooms)
Omega is EXTREMELY big floor (taking all possible spaces on the map), and it's always with Curse of the Darkness applied to it. Doors on the floor can't be destroyed by explosions, and every door is spiked (hurting player every time they walk through it; if player has flying, damage will be taken when walking back through the door).
Possible room layouts include:
*4 random Deadly Sins + 2 Super Deadly Sins (of the same type)
*5 random Deadly Sins + random 1 Super Deadly Sin
*4 Fistulas + 1 Teratoma
*3 Teratomas
*4 Harbingers + Conquest/Headless Horseman
*4 Pins + 2 Scolexes
*6 Monstros + 2 Monstros II
*4 Monstros II
*6 Dukes of Flies + The Husk
*4 Husks
*3 Hollows
*3 Bloats
*4 Lokis + 1 Lokii pair
*3 Lokii pairs (6 halves)
*5 Gemini pairs + 1 B. Ovum pair
*4 B. Ovums pairs
*2 Fallens
All of the above can be accompanied by explosive Leeches, demonic Babies (see Fan Ideas/Enemies and turrets (both green and gray varietes).
Non-enemy rooms in Omega include:
*spike checkerboard room (every other tile is spiked)
*Red Poop room (entrances are blocked by Red Poop; same as the Chest)
*Red Chest blocked by 2 keyblocks (can't be accessed if player can fly)
*Red Fire room (the same layout as occassional "devil" fire rooms earlier)
*The boss of Omega is "Him" (see Fan Ideas/Enemies for details).
==Time==
By unknown
Unlocked by unlocking The End. 
Sometimes when moms heart/it lives is defeated, there will be nothing but a giant white clock on the ground infront of you. If you touch it, the screen turns white and you will spawn in a room that is the center bottom room. There will be a chest infront of you containing 1 bomb. Never different. The dungeon is just completely white rooms with a unnerving TIK TOK sound in the background. Sometimes clocks will be drawn on the walls. There are no doors except for up, and in the second room you will either encounter:
*CHAD and the Slenderman
*GISH and Krampus
*2 Lokis and Scolex
After that, you will get 1 free heart and a door will appear near the top.
In the third room it will be the 2 of the above that you did NOT fight.
Same thing, Door at the top and 1 free heart.
In the fourth room it will be the LAST pair of bosses you didn't fight. This time there will be hearts all over the room and the boss door will be black. Be prepared, because the isaac of this floor is about to give no mercy to you. Upon entering the room... You will fight The HATRED.
After defeating him the usual chest will appear. When it is opened, there will 2 pictures that isaac looks at.
The first one shows a black figure floating in air saying something to isaacs mom.
The other shows isaac in the basement where a purple skull glows faintly in the background.
What is all of this about you say? Well, you have unlocked a new floor, MEMORIES which is basically TIME on super hard difficulty. It also explains the mysteries behind these pictures.
==The Core==
By unknown
The core is unlocked by defeating It lives and Satan in a single run
When you start the core, you will be given 2 chests, 1 has a full health pill, while the other has 2 sprit hearts
The core is basicly a line of 6 rooms, excluding the boss room
In the five rooms, you can experience these boss combos
*Monstro 2 and The Carrion Queen
*Larry Jr. and The Husk
*Biocysalyst and Chub
*The Mask of Infamy and The Duke of Masks (see boss ideas)
*The Fallen
*Super Lust,Super Wrath,and Super Gluttony
*(Rarely) Ultra Pride
*2 Fistulias
And when you finally reach the bosses room, prepare to die because your're gonna face LOKIE!(Boss ideas for info)
==Nightmare==
By KirbyCZ
How to open a Nightmare?:
You must defeat Issac 30 Times and ??? 20 Times. It will open a new Chest next to The Chest. The new Chest will like a chest from curse room.
And to enter you will need Polaroid(of course).
Nightmare is very extremly hard floor, in most of the rooms will be bosses(medium chance of spawning Champion version), in other champion version of better enemies.
On Beggining you will get 6 Red Chests with Items.
Edit:The damage is tripled(3 Hearts if someone hit you).
There is Bigger room than normal.
Rooms:
*7 Monstros
*9 Duke of Flies
*7 Gemini(Steven)
*14 Larry Jr.
*8 Widows
*11 Pins
*7 Blighted Ovums
*7 Gurdy Jrs.
*6 Fistulas(all not only parts)
*4 Gurdys(Special big room)
*10 Peeps
*7 Chubs(Chad)(a Little bigger room)
*6 Carrion Queens
*9 Husks
*14 Hollows
*7 Wretcheds
*9 Monstors II.
*8 Lokis
*7 Gish
*5 Moms
*9 Mask of Infamys( You will have fun for 2 Hours :D)
*9 Daddys Long Legs
*9 Bloats
*8 Triachnids
*9 Scolexs
*8 Blastocysts
*4 Mom's Hearts( Not It Lives)
*2 It Lives
*4 Teratomas
*16 Lokiis
*3 Satans
*3 Isaacs
*2 ???
*9 Fallens
*10 Krampus
*5 Horsemens
*6-9 Sins in the room
*5-8 Super Sins in the Rooms
*4-6 Ultra Prides
...and Final boss will be Destroyer.
If you have a really really small luck you have chance to will get a Special room, where is twice enemies and bosses.
Normal Enemies:
I said in beggining you will get only better enemies in 15-40
If you kill Destroyer you will get a other ending you didnt see the photos you will see the movie from video recorder.
Reward:
Soul Penny-Defeting Final Boss with ???
More Soon...
==Happy World==
By unknown
You need the wafer, the nail and nuns habit to complete this.
You will find this floor after beating the floor Nigthmare.
Rooms:
*16 Monstros
*20 Duke of Flies
*14 Gemini(Steven)
*17 Larry Jr.
*13 Widows
*12 Pins
*9 Blighted Ovums
*11 Gurdy Jrs.
*6 Fistulas(all not only parts)
*3 Gurdys(Special big room)
*10 Peeps
*7 Chubs(Chad)(a Little bigger room)
*5 Carrion Queens
*9 Husks
*16 Hollows
*8 Wretcheds
*12 Monstors II.
*11 Lokis
*9 Gish
*6 Moms
*10 Mask of Infamys( You will have fun for 3 Hours :D)
*10 Daddys Long Legs
*9 Bloats
*9 Triachnids
*10 Scolexs
*8 Blastocysts
*5 Mom's Hearts( Not It Lives)
*3 It Lives
*5 Teratomas
*18 Lokiis
*4 Satans
*3 Isaacs
*3 ???
*10 Fallens
*10 Krampus
*6 Horsemens
*9-13 Sins in the room
*7-11 Super Sins in the Rooms
*6-8 Ultra Prides
Final boss is just like ??? but with 15 times more hp, all shots will be homing, instead of spawning angel fetuses it spawns extremly many I.Blobs
==Isaac's Room==
By unknown
You will find this floor after beating the floor happy world.
You can't use space bar items!
Rooms:
*5 ???s
*20 bloats and 1 ???
*20 knigths with 10 bloats and 3 teratomas
*99 fat flies
*1 gurdy jr with 100 times more hp than normal and 2 widows
The boss will be Larva.
==Golden Temple==
By unknown
Not really a required floor, and it is more so a secret floor which can only be reached by using the shovel in a secret room EXACTLY where the dead greed at the top of the room is. By doing this, you are sent to Golden Temple, which has walls that are similar to that of the Basement, and flooring similar to the basement, but it is golden and shiny. 
Like most floors, there is a Golden Temple 1 and a Golden Temple 2. Most of the enemies encountered in this floor  are based on Greed with some existing, and some newer Greed-like enemies, including Greed himself. While going through this floor, one may notice that there are two item rooms per floor, and two shops, though it counts as one floor, not an XL floor, meaning through the Golden Temple secret chapter, you can get four item rooms in those two floors, and two shops. You can also notice the abundance of money dropped on this floor. The two bosses encountered are champion versions of the next chapter where you originally used the shovel on to get to this area, so if you were in the Basement and used to the shovel to get to the Golden Temple, you'd encounter Champion Husks and Peeps and such. 
It is expected to gain a lot of money during these floors and a lot of various drops. When you finish Golden Temple 2, you are brought to the next chapter from where you originally used the shovel, so if you used the shovel in the Depths 1 or 2, once you finish the Golden Temple, you'd be brought to the Womb.
In the Golden Temple, things do a full heart of damage regardless of where you are in the required game. 
Suggested by Ninjastyle124!
==Red Chest==
By Ninjastyle124
This is another secret and unrequired floor which you can only go to if you beat Blue Baby with the Forget Me Now, and once Blue Baby is dead, you use the Forget Me Now. As this is a secret, and unrequired, it isn't necessary to beat the game by going to this floor and you are unlikely to ever go to it, so it's just a secret and doesn't count towards 100%ing the game. 
What you will notice is that you are in a similar room to the spawn room to the chest, though it is full of Red Chests instead of golden chests, and the walls and floors resemble a Red Chest. Upon opening the Red Chests, they give you a random Devil or Angel item instead of spiders or spirit hearts.
The enemies in the Red Chest, and layout is definitely harder than even the Chest. The boss of the Red Chest is pretty much a red reskin of Blue Baby and Isaac but more absurd and ridiculously OP. Instead of just being a touch stronger than Isaac like Blue Baby, this reskin brings it to an entirely different level, and unexpectedly at half health will change boss style altogether, probably unexpected considering the last two bosses you will encounter that are similar. The boss in this phase has every item you have, but stronger, and runs around like a normal mob, but with an advanced AI thus you have to be smart or else it will kill you and it will literally move on its own, not as a mirror.
==Eaden the Sea of Sin==
By WitherSnow
When you beat a boss in either necropolis, catacombs or utero you will find a room agacent to the boss room.It has a statue of Mom's leg and heel, as if it were in the Mom boss fight but grey and made of stone. In the room is a trapdoor that leads to the sea of sin and the room is colored the same stone color but with a few pink gemstones randomly scattered on the walls and floors but they're only there for astetics. There is a trapdoor that leads down to eaden. The floor is basicly a puddle of water with the walls giving off a sewer ish type of design. You can find new enimies such as crabs dying starfish catfish and of corse bosses from previos floors.The boss of the first floor is either pin, duke of flies, famine,2 of the deadly sins or a new boss called Lobstro. (Title not finalized.) The interesting thing is at the beginning of each floor the hearts that you didn't pick up reapear as dimes for you to use on beggers. After dropping down you will notice you are underwater where the mechanics are no different. However new enimies spawn such as starfish, sharks, eels, swimming catfish and anchors hanging from chains. The boss of floor 2 is the octipin. The tenticles come from holes in the boss room. Afterwords the final trapdoor is revealed and the water sinks down to a puddle. You go down a crack in the floor that is opened and see a cutscene of the cheracter riding a waterfall.. Now we are in an undersea cavern. There ilittle rooms in this floor The only thing standing in your way is a locked boss door which needs a key which you can find in one of the rooms. In the boss room is Eve.. Beating her unlocks the Forbidden Apple.It When used it gives us 2 heart containers and multiplies our damage by 2. It is a spacebar item. The charge bar is used a life bar for the item..When we beat eve for the third time she gives us a poleroid. Not the poleroid bit another poleroid.When we appear at the title screen we see eve in a circle all alone. Unless you beat Isac or ???. Samson can be found in the prison mentioned above.
Some possible room layouts:
*pin and 2 crabs
*2 dying starfish and a crab
*3 catfish and Monstro
*Duke of flies and 6 crabs
*lumps and 2 heart and masks.
*2 widow and 1 knight
==The Garden==
By WitherSnow
In the depths, caves or womb we should see that same room mentioned above. However instead of a way down we have exposure to the night. Walk into the night and you are in the garden. It is night out and there are a few enimies to discuss.
*Bees
*Garden snakes
*Hedgehogs (And i mean HEDGE hogs.)
*Fluor
There are gates that section off each part of the garden. The boss is Magdiline. She has the same pattern as Isac except she uses biblical items such as the halo, the habit ,the book of shadows and the angel of babylon item.(new) After defeating maggie we get the golden insurence. This turns angel rooms into cathedral spots and devil rooms into regular angel roooms when spawned. After beating her the third time we get another poleroid. Magdiline stands between ??? and Samson.
Some room possibilities:
*Pin and Monstro
*Widow and 2 pride
*4 Fluor and a widow
*6 bees and bloat
*3 garden snakes and 2 war.
*Pestilence and 2 Lokki
*6 pooter and 2 blue clotty 
*5 Blastycist and 2pink widow.
*3 trite and 1 Steven
*4 chad and 1 Champion braIn
*11 champeon pooters and 2 Membrains
*4 holy leeches and 2 lumps
*Pin and 5 lumps
The fallowing set of bosses will be spawned durring the Magdiline boss fight on form 2) She will fly up until the boss is defeated.
(If teleported from womb)
*Scolex
*Mom
*Blastycyst
*Mom's heart (Final stage)
If spawned from depths:
*Mask of infamy
*Mom
*Bloat and Duke of flies
*Daddy long legs
If spawned from caves
*Chub
*The husk
And now after we have covered all of that it's time to go fight Cain in the...............................
==The Bottom==
By TacoGuitarPlayer
This is the, basically, The Chest for Shoel. It has bright red walls with flames on it and blood dripping from the top. It is bigger then The Chest, but slightly less brutal, as it is designed to slowly were down the player to then make the player fight, a demon Isaac. The more intersting part is the endings, which are triggered when you walk over the unopened trap door after beating the boss. One of them is the ending where Isaac keeps running from Mom or his problems (your choice), and the narrator says "Isaac ran until his life ended. This is the end. Isaac knew there was nowhere to go. Nowhere to run, but he ran anyway. This is the end for poor Isaac." This unlocks a endless mode if you go there again in which you enter Limbo. This achieved by making a deal with the devil. The second ending in which the trap door opens and shows nothing, but ground and then Isaac goes to he fetal position and continues to cry. This is achieved by not making a deal with the devil and not taking a gift from the angel, or taking both. The third and final ending is the one when the trap door opens a bright light over takes the screen. Then a cut scene show Isaac going up a beam of light. This is achieved by only taking a gift from the angel.
==The Sin Room==
By unknown
Found after you defeated the challange boss room at extremely rare chance (5%)  and cost one soul heart, is unlocked after you beating Sin World, and have 3 Devil Items, and have a ultra sin to defeat.
*Sin Injection (common)
*My lovely sin (Very Rare)
*Heart Attack (common)
*SoulStealer (rare)
*Book Of Belial (common)
*Mons contact ( rare)
*The Book of Sins (very common)
*Monster Manual (very rare)
*The Nail (rare)
*Necromicon (common)
*Blood Rights (rare)
*The Candle (common)
Only appear in catacombs and necropolis.
==Limbo Room==
By unknown
Found as a rare chance (25%) instead of the top secret room. Includes 1 rare limbo item or 2 common limbo items. (see below and Items)
*Ram Horn (rare)
*The Quad Mark (common)
*Dark Claw (common)
*Technology 3 (rare)
*The Fin (common)
*SoulStealer (common)
In womb II a limbo room will contain a trapdoor down into Limbo (the trapdoor will have souls coming out of it.)
==Laboratory==
By unknown
Requirements: x1 Key
This room can sometimes appear in a floor, similar to a Library. Inside, there will be a button on the floor. When stepped on, it summons three waves of enemies similar to a challenge room. At the end of it, though, you get a random item. The item is themed to technlolgy and science. Items that can appear in the Lab are listed below.
OFFICIAL GAME ITEMS
*Technology
*Technology 2
*Doctor's Remote
*Teleport
*X-Ray Vision
*Battery
*9-Volt
*Gamekid
*Robo Baby
==The Chest Room==
By unknown
Requirements: x1 Key
This room has nine gold chests. Two of them contain something (Items, money, etc.), five of them contain nothing, and two of them contain a Super Troll Bomb.
==The Garage==
By unknown
Appears randomly as an end room, may cost a key to enter but may also spawn unlocked
Door appears as a garage door with small windows and occasionally a padlock when locked.
Contains two "refilling stations", both of which require coins.
The left station will randomly drop hearts when used like a beggar.
The right station will refill item charges, may recharge 0, 1, 2, 3, or 6 bars.
The center of the room will always contain a random chest, or on rare occasion a free themed treasure such as the battery or the 9 volt, teleport! or the Doctor's Remote.
==Trading room==
By unknown
The chance for that room to spawn is 25%. In the middle of the room there is a box. You can put there one of your passive and activated items and then leave the room. When you return and open the box, you'll find an other item which you can collect.
==Bedroom==
By unknown
A room that has a pedestool in the middle contaning a mom item or dads key and two chests that randomly give trinkets it has a beige carpet purple and green striped walls and two desks at bottom that when blowen up have random pickups.
==The Forgotten's Chamber==
By unknown
Requirements: 3 soul hearts
====The forgotten's chamber is a room where you encounter The forgotten. He is a boss in Fan Ideas/enemies, this room is like the secret room, but really rare, and hard to find. He is a secret boss, and when you kill him, you get The Rusted Nail, turning you into the 1st form, when you're 50% close to death, you turn into the 2nd form, then at half a heart, you turn into the final form.====
==Chest (Super Secret Room)==
By ZangiefB
This variation of the Super Secret Room is basically the same as the starter room in The Chest: four gold chests each containing items with the background of the Chest.
==$$$ Room==
By Pillbox15
In this room, a random coin related item, trinket, or many coins will be offered here for the taking. However, there is a relatively high chance to run into Greed/Super Greed here *if you are really unlucky you could run into 2 Greeds*.
Category:Bum