Curses

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:

Chance
Your odds of getting a curse vary with progression, increasing over time.


 * All curses have an equal, 1/6 chance of occurring.
 * If Curse of the Labyrinth is picked on a floor it cannot spawn on, such as the second floor of any chapter, Greed Mode, or on any chapters post-Womb, no curses will be active for the floor.
 * This makes the chance of getting cursed on floors without Curse of the Labyrinth 1/6, or 5/12 for Hard Mode.

Trivia

 * Of the three curses that returned from Wrath of the Lamb, (Labyrinth, the Lost, and Darkness), two of them — the Curse of the Lost and the 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. The 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.