Each time you reach a new floor, there is a small chance to receive a curse, making the floor much more difficult to complete. Each curse only lasts for the current floor. The possible curses are:
|Curse of the Blind||All items are replaced with a question mark and are not revealed until they are picked up.|
|Curse of Darkness||The floor is much, much darker, and is only barely lit by the player's natural aura. Occasionally rooms will be filled with swirling clouds of what could be fireflies or glowing motes of dust. Fire, explosions, and lasers will all cast light as normal, as will red creep.
The aura of light around Isaac is now much larger, but the darkness outside it is much darker.
|Curse of the Lost||Removes the map from the HUD. Same effect as the Amnesia pill.
Also increases the possible total room count of the current floor to the size of the next floor.
|Curse of the Maze||Entering a new room (including teleporting) will occasionally take Isaac to the wrong room, with a screen-shake and sound effect to indicate the jump. For example, entering the room on the right may instead take Isaac to the room on the left. Occasionally, discovered rooms can swap contents, without a screen-shake or sound effect.
The wrong-room effect can now only take Isaac to undiscovered rooms.
|Curse of the Unknown||Removes Isaac's health from the HUD, leaving the player unable to see how many hearts remain of any kind. Health will still be tracked as normal, including Soul, Black, and Eternal Hearts. When Isaac is down to half a heart, it is still marked by urine when entering a room.|
|Curse of the Labyrinth||Appears only on the first floor of a chapter. Makes the floor an XL floor, which contains two Boss Rooms, two items and counts as two floors. If this happens in either Basement, Cellar, or the Burning Basement, both Treasure Room doors will be unlocked.|
|Curse of the Cursed||Changes normal doors into cursed doors. Found only in the Cursed! challenge or enabling the "CVRS ED" seed.|
|Curse of the Giant||Combines normal sized room into 2x2, 1x2, 2x1 or L-shaped rooms while narrow rooms are not affected(further confimation needed). This curse currently isn't achievable naturally in game.|
Your odds of getting a curse vary with progression, increasing over time.
|Killed Mom 5 times||1/30||1/5|
|Killed Isaac||1/5||1/2 (1/3)|
- All curses have an equal, 1/6 chance of occurring.
- Curse of the Labyrinth can spawn the same boss in both rooms on one floor.
- Because Curse of the Labyrinth causes the two floors in a chapter to merge, it is possible to lower your Devil Room encounter chance in Basement I, Cellar I, or Burning Basement I.
- With the Curse of the Labyrinth, it is possible to teleport into the second Boss Room and completely skip the first.
- If Curse of the Labyrinth takes effect during Chapter 1, taking the door that spawns after the second boss room will lead to Downpour II or Dross II.
- If Curse of the Labyrinth merges Downpour or Dross, there will be two "mirror" Boss Rooms.
- If Curse of the Labyrinth merges Downpour, Dross, Mines, or Ashpit into an XL floor, the special rooms leading to Knife Piece 1 and Knife Piece 2, and their associated gimmicks, will still appear.
- Curse of Darkness can be made somewhat easier by increasing the gamma setting in the game's options.
- XIX - The Sun can now remove Curse of Darkness for the current floor.
- Curse of the Unknown does not affect The Lost, as he is, technically speaking, perpetually under its effect anyways.
- Curse of the Maze can be used to enter locked rooms without spending keys. It can also be used to enter Curse Rooms without spending health, Arcades without spending coins, Bedrooms without spending bombs, Secret Rooms (without spending bombs), and Boss Rooms. Be warned, though, as it can teleport Isaac elsewhere when trying to enter a Curse Room, forcing him to take a full heart of damage to enter it (unless the player has some form of flight).
- When Curse of the Maze triggers, it takes into account the direction the room was exited through. For example, if Isaac leaves a room by a door on the right wall, it can only take Isaac to a room that has a door on its left wall. (also works with teleporting)
- Curse of the Maze can only swap rooms that have doors in the same spots as each other, including (Super) Secret Room doors.
- If you know two rooms swapped places and one of the rooms has a wall where the other had a door, a secret room is guaranteed to be there.
- Curse of the Maze may otherwise interfere with teleportation cards, but Joker is unaffected.
- Curse of the Maze can teleport Isaac to the same room he was just in.
- Curse of the Maze now only teleports Isaac into uncleared rooms.
- XIX - The Sun and Rune of Ansuz do not counteract the effect of Curse of the Lost.
- With Curse of the Blind active, leaving and re-entering a room which had a revealed item will change the item back to a question mark.
3DS Curse of the Lost can be countered, as the player can draw a map on the touch screen.
- Of the three curses that returned from Wrath of the Lamb, (Labyrinth, the Lost, and Darkness), two of them — Curse of the Lost and Curse of Darkness — have different effects from Rebirth onwards. Namely, the Curse of the Lost's old effect (which simply made the floor as big as a floor that was one 'tier' higher, meaning a Basement as big as The Caves, or a Depths as big as The Womb) was dropped entirely, the Curse of Darkness's old effect (removal of the map) was given to the Curse of the Lost, and the Curse of Darkness was given the dark-floor effect. Curse of the Labyrinth, meanwhile, remained untouched.
- Curse of the Giant was a curse in Antibirth, but was removed in Repentance. However, it is still fully complete in the game files, but cannot happen in game. This was because the Curse led to some rooms that could be incredibly unfair. Kilburn (the lead developer of Repentance) was going to add a system that determined the fairness of the 2x2 room, such as limiting the number of enemies. However, it was too complicated to be finished in time, so it was scrapped. He said that it might eventually be completed, though.
|Bug!||Curse of the Maze can still take you to already explored rooms|
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|