The Secret Room (see also: Super Secret Room) typically contains no enemies and 3-9 Coins (usually pennies, with slight chances for nickels and dimes), a slot machine, or an item. The "sin" mini-boss Greed will sometimes appear in a secret room instead - The Compass will show if he resides there (this is impossible in levels before The Depths or Necropolis, at which point all floors have a 50% chance of containing him inside).
In the Secret Room, the track Respite plays in the background.
Secret room can contain:
- 3 random Coins (very common)
- 6 random Coins (very common)
- 9 random Coins (very common)
- Slot Machine (common)
- Fortune Telling Machine (uncommon)
- Greed (uncommon) or Super Greed (rare)
The room will rarely contain one of the following Items:
- Bob's Rotten Head
- The Book of Belial
- Dad's Key
- Epic Fetus
- My Little Unicorn
- Raw Liver
- Spider Bite
- We Need to Go Deeper!
Some of these items are more common than others.
Locating the Secret Room
The room is normally unmarked on the map, although the Treasure Map will show it automatically. The player must bomb the wall of an adjacent room (in the middle, where a door would be) to gain access. X-Ray Vision will automatically reveal entrances, thus foregoing the need to bomb. When you have the Spelunker Hat, a chime will play when entering such a room, otherwise its location must be guessed.
The Secret Room tends to border 3 or 4 normal rooms, a good indication of where to try. It can however border on only 2 rooms and, though rare, it is possible for the Super Secret Room to be counted as one of the prerequisite side rooms, causing the secret room to border only one normal room.
Entrances created to the Secret Room close upon leaving it (as of Rebirth, this is no longer the case). The player can bomb into other adjacent rooms from inside, but without X-Ray Vision will not be able to enter Boss or Challenge rooms in this manner. Just like any other mini-boss room, if Greed inhabits the secret room you will not be able to bomb your way out through any of the other walls.
Usually you can find secret rooms when you look at the map. If you see a pattern of rooms enclosing three out of four sides of a square, similar to a 'horseshoe', this usually indicates a secret room. There is a small chance where such pattern does not exist in normal rooms. In cases like these, the secret room borders two normal rooms.
- It is possible for the Secret Room to be inaccessible, if it only borders the Boss Room and the Miniboss Room of the floor.
- If the secret room is next to the starting room or next to the boss room, it will show a door and quickly change to a flat wall.
- It is possible to find enemies other than Greed/Super Greed, although extremely rare, in the Secret Room.
- It is possible for the Secret Room to not exist on some floors, but this is very rare. In such cases, using XVIII The Moon will simply teleport you to a random room on the floor.
- The entry to the Secret Room may be visible for a split-second upon entering an adjacent room (observed in start room).