Debug Rooms/Increase item and level
Codes
[M] Must Be On
99A1BD8F862B
EBF661EEF0DB
DAC993B258D6
Enter Debug Room 1 [L+B+Up].
D80EFAC39F06 FFF511346040
D80EFAC39F06 D64897821A14
Exit to Vale Sanctum [L+B+Down]
C8443E41BD0D FFF511346040
C8443E41BD0D 08667B44BCAB
C8443E41BD0D 0B26410D38BB
NPCs
Statue
Brings up a menu where the player can select any item in the game to place in their inventory.
Man
Brings up a menu where the player can select any Psynergy and view its name and description. However, closing the menu will cause random memory corruption. This will commonly corrupt the sprites of Isaac and other map NPCs, but can also have numerous other effects including crashing the game.
The cause of the memory corruption is an uninitialized variable, which the game expects to be a pointer into memory it can write to. However, since it's never initialized, the game will instead interpret whatever arbitrary value already exists in the variable's respective CPU register as a memory address, and write data to that address. This means that this effect can corrupt any location in RAM, though in practice it's difficult to control.
Giant Cat
Brings up a menu where the player can increase Isaac's level by 1 and 5 with the A and Start buttons, respectively.
Speech Bubbles
Both can be talked to and they say, "I won't stop you, but I wouldn't go unless I had business there. I'd go to Tolbi and watch Colosso. That's what I'd do." This is what the guard at Gondowan Passage says to Isaac if he tries to cross before competing in Colosso.
Menardi
At the top-left corner of the map; only her feet are visible. Brings up a menu where the player can view all the facial portraits in the game.
Saturos
Hidden off the edge of the map, directly above Menardi. Brings up a menu where the player can view the icons for every item in the game.