I AM ERROR

The I AM ERROR room is a rare room that isn't connected to any other room on the floor and is reached through glitches or as a failsafe for an impossible event (like using Blank Card on ? Card, which loops on itself infinitely without a failsafe).

I AM ERROR rooms are chaotic and often contain multiple items, pickups, beggars, and/or powerful enemies. There are no doors to leave, but always an exit to the next level (with few exceptions) and at least one unique shopkeeper (pictured above) with a text bubble that reads "I AM ERROR".

The trapdoor will always be open, even if there are enemies in the room.

Accessing the I AM ERROR room

The only items/effects that can bring Isaac to the I AM ERROR room are Telepills, Undefined, Teleport 2.0, Red Key and Blank Card + ? Card. (This consumes Blank Card and ? Card)
Undefined is the simplest method, as it has a decent chance to teleport the player there.
Using Red Key on the 13x13 boundaries of the map will create a 1-way door to the I AM ERROR room, and displays no icon on the map upon opening.
- No red door outlines will appear on the normal floor's boundary walls, meaning the I AM ERROR room can only be entered from another Red Room. At least 2 uses of Cracked Key are needed to enter if you don't have access to Red Key.
Telepills have a very, very small chance of teleporting Isaac to the I AM ERROR room.
Using Teleport 2.0 when all rooms on the floor have been explored (including the Secret Room(s), Super Secret Room(s), and the Devil Room or Angel Room) sends you to the I AM ERROR room.
The I AM ERROR room can be reached by leaving a Crawl Space through an unintended direction. This will always bring you to an error room, even when all other methods stop working.
- Blank Card + XXI - The World?, Clear Rune + Rune of Ehwaz, We Need To Go Deeper!, and Mom's Shovel offer consistent methods of creating crawl spaces.
- Use 4 size downs, 2 speed, and crash into the floor below the entrance ladder or 3 size downs and the left and right walls using flight.
  - One makes you smaller is the easiest way to acquire multiple size downs, and while you can exit the crawl space using listed minimums, it requires a lot of patience sometimes. Pluto/Inner Child are equal to 4 uses of the pill.
  - It is possible to clip through the floor with 4 size downs and any speed, but the slower Isaac is, the more difficult it becomes to do so.
  - It is also possible to exit through an unintended direction using A Pony / White Pony and 1 size down, albeit rarely. Significantly more common with 2 or more size downs. The speed stat does not matter since the charge-speed is a flat velocity.
  - You can use Spin to Win, 2 speed & flight just by themselves to exit, bouncing off the far left and right walls and timing turning around after each bounce to build up speed and eventually exit.
  - Tainted Forgotten can be thrown outside the Crawl Space provided Tainted Soul builds up enough velocity, resulting in accessing the I AM ERROR room.

The only way to access the I AM ERROR room on Chest, Dark Room, The Void, Home, Corpse II, or the Dad's Note floor is through a Crawl Space.
- Chest and Dark Room's I AM ERROR room contain a portal to The Void.
  - If The Void is not unlocked, it will instead contain a trapdoor that brings Isaac back to the floor.
  - If the I AM ERROR room is encountered during a daily challenge or a regular challenge, it will instead contain a trapdoor that will reset the floor. If you have been given a Mega Satan key for the challenge, you will be supplied with another one on the next floor.
- Corpse II's I AM ERROR room has a trapdoor that brings Isaac back to the floor.
  - In the rare event of accessing I AM ERROR on Corpse XL and encountering a trapdoor in that error room, Isaac is taken to a new floor which attempts to load then the game crashes.
    - This can be viewed by enabling the LABY RNTH seed and getting into the Corpse XL Error room. The loading screen will display Home's floor icon and the game will crash after.
- The Dad's Note floor is the same as a regular Mausoleum/Gehenna II I AM ERROR room, leading to Womb II.
- Home and The Void's I AM ERROR room simply contain a trapdoor that restarts the floor.
The I AM ERROR room cannot be reached anymore in Chest, Dark Room, or the final floor of the daily challenge.
Entering the exit of an I AM ERROR room in the Chest or Dark Room will restart the floor.
During the Ascent, the I AM ERROR room will contain a beam of light instead.

Room Contents

The following room maps were made using Basement Renovator for cleaner viewing.

ID	Weight	Contents
0	1.0	Two items.
1	1.0	An item and nine random pills.
2	1.0	An item and 16 random coins.
3	1.0	An item, four random cards/runes, and ten urns.
4	1.0	An item and four Chests.
5	1.0	An item, two pickups/items for sale, and seven random coins.
6	1.0	An item, four pickups/items for sale, and two Golden Poops.
7	1.0	An item and an Eternal Heart, Red Heart, Soul Heart, and Black Heart.
8	1.0	An item, two random keys, and 6 Locked Chests.
9	1.0	An eternal, red, soul, and black heart, a Key Ring, a Double Bomb, a regular, locked, and Red Chest, a Lil' Battery, two random pills, and a random card.
10	1.0	An item and four trinkets.
11	1.0	Four soul hearts.
12	1.0	An item, eight shopkeepers, and 12 Fly.
13	1.0	Four shopkeepers, six keys, and two Key Masters.
14	1.0	48 Poops and 2 golden poops.
15	1.0	An item, four extra error shopkeepers, and two Rag Men.
16	1.0	11 Reward Plates.
17	1.0	A Corny Poop, 14 Attack Flies, and 18 random pickups/items.
18	1.0	Two items, eight shopkeepers, and Super Greed.
19	1.0	Two items and a Shop Restock Machine.
20	0.1	Eight soul hearts and 12 Blue Gapers.
21	1.0	12 Fire Places and 7 Spiked Chests. It is possible to enter the room on a spiked chest and immediately take damage.
22	1.0	An item, six keys, two Eternal Chests, eight Blue Fire Places, and two Angel Statues. The angels will not drop key pieces if defeated.
23	1.0	An item, two Lucky Pennies, two black hearts, a Gold Heart, two Black Runes, four spikes, six Red Fire Places, and two Devil statues.
24	1.0	Five Grab Bags, two Lil' Batteries, and four random pickups/items.
25	1.0	A Donation Machine, poop, two Beggars, two Blood Donation Machines, and two Beds.
26	0.1	Two items, two golden poops, four Rainbow Poops, and 23 random pickups/items.
27	0.1	Two pickups/items for sale, nine poops, and six flies.
28	0.1	An item, two Bulbs, and four Black Poops.
29	0.1	Six Gold Hearts (four of which are behind Spiked Rocks), four extra shopkeepers, and a Golden Troll Bomb.
30	0.5	Four keys and two Mega Chests.
31	1.0	A Nickel, eight random coins, six poops, a Beggar, and a Rotten Beggar.
32	0.5	Two keys and four Old Chests.

Notes

Once Isaac arrives at the I AM ERROR room, the only ways out are the trapdoor to the next level or another teleport. As the I AM ERROR room is randomly reached, this could force Isaac to skip Treasure Room and/or Boss Room items if they hadn't been picked up before, and if he cannot teleport again.
Items in the I AM ERROR room will be from random item pools.
Once Corrupted Data is achieved (beating Delirium as Tainted Eden), items that spawn in this room have a chance to be randomized as if affected by TMTRAINER.
Using Undefined on ??? always sends the player to the error room, as there are no secret rooms on this floor.
If a Crawl Space is spawned in the I AM ERROR room, Isaac will return to the room he was in before being teleported to the I AM ERROR room upon exiting the Crawl Space.
Using the trapdoor in the I AM ERROR room can allow Isaac to reach levels not yet unlocked, like Sheol or Cathedral.
Using the trapdoor in Chest or the Dark Room will restart the level, similar to the effect of the Forget Me Now, and as of patch 1.05, the floor will generate a different layout upon restarting. The door to Mega Satan will be locked if it was previously opened.
The chests present in the I AM ERROR room while on Chest and Dark Room always contain items.
Using the Rune of Jera in most of these room configurations can allow Isaac to duplicate a very large amount of pickups, making Jera especially effective in this room.
If Isaac is teleported to a Devil Room or Angel Room from an I AM ERROR room (e. g. by using Joker), exiting the room will return him to the room he was in before entering the I AM ERROR room.
If Isaac uses IV - The Emperor? card inside an I AM ERROR room, exiting the boss room will return him to the room he was in before entering the I AM ERROR room.
Entering the I AM ERROR room from Womb/Utero/Scarred Womb II will randomly result in a trapdoor or a beam of light. Isaac may have to end his run early in the Cathedral/Sheol.
It is probably not a good idea to go to the I AM ERROR room on Depths/Necropolis/Dank Depths II before getting The Polaroid/The Negative, because then you can't go to the Chest or Dark Room, having to end the run in Sheol or Cathedral.
- Reaching another I AM ERROR room in the above-mentioned levels would allow continuing the run beyond them, even lacking the prerequisite items.
- Note that the 12th reward and onward in a Sacrifice Room has a 50% chance to send Isaac to Dark Room. This may be useful if an I AM ERROR room locked Isaac out of The Negative.
- This rule also applies to Isaac when trying to reach an alternate floor from a main floor (Downpour II from Basement II, etc.). The I AM ERROR room will always send him to a regular floor (Basement II to Caves I, etc.) and Isaac will not be able to pick up the necessary progression items needed to reach Corpse.
  - However, in Mausoleum/Gehenna II, if Isaac kills Mom's Heart first, then enters the I AM ERROR room, the trapdoor inside will lead him to Corpse.
- This also applies to reaching Home. The I AM ERROR rooms of Depths II, etc., will instead send Isaac to Womb I, etc., and he will not be able to enter the Strange Door.
There is a rare Closet room in Depths and Necropolis containing an I AM ERROR shopkeeper. This is not an I AM ERROR room, and can be exited normally.
There is a Super Secret Room that looks like an I AM ERROR room. This is not an I AM ERROR room, and can be exited normally.

Trivia

The I AM ERROR room is a reference to an infamous quote in the NES game Zelda II: The Adventure of Link, where a citizen from Ruto introduces himself with the sentence "I AM ERROR".

Bugs

Bug!	If isaac enters an I AM ERROR room in the first room of the first floor (possible with Eden), and have not entered any rooms yet, using Glowing Hourglass will send him back to an identical starting room, with all of his starting items missing, including the Glowing Hourglass. This also affects items gained from Eden's Blessing.