Doom Codes -

Map all lines:
Pause the game and press Triangle(2), L2, R2, L2, R2, R1, Square. To confirm correct code entry, a message will appear on the bottom of the viewing window and will disappear the game is resumed. All walls and boundaries will appear on the map for the current stage.

Map all items:
Pause the game and press Triangle(2), L2, R2, L2, R2, R1, Circle. To confirm correct code entry, a message will appear on the bottom of the viewing window and will disappear the game is resumed. All objects including enemies, items, weapons, and secret switches will appear on the map as blue triangles.

Invincibility:
Pause the game and press Down, L2, Square, R1, Right, L1, Left, Circle. To confirm correct code entry, a message will appear on the bottom of the viewing window and will disappear the game is resumed. Your character will be invincible, however unlike the invulnerability power-up, your screen will not turn white.

Weapons, ammunition, and keys:
Pause the game and press X, Triangle, L1, Up, Down, R2, Left(2). To confirm correct code entry, a message will appear on the bottom of the viewing window and will disappear the game is resumed. All weapons, ammunition for them, and keys for current level will be available.

Level select:
Pause the game and press Right, Left, R2, R1, Triangle, L1, Circle, X. If the code was entered correctly, a menu will appear in the top half of the viewing window. Press Left and Right to select a level, and confirm your entry with Square, Circle, Triangle, or X.

Transparent walls:
Pause the game and press L1, R2, L2, R1, Right, Triangle, X, Right. Your character may now see through one layer of wall or sprites.

Random levels (version 1.0):
Enter DOOMMNLxxx or H3LL1SHxxx, where xxx the same character such as !!! or 666, at the password screen. The game will start at a random level with an unusual amount of ammunition, armor, and life.

Level	Health	Armor	Weapons	Password	Title
Ultimate Doom
02	125%	200%	All	CR!3WDD3DB	Plant
03	200%	200%	All	3JJCMK8W64	Toxin Refinery
04	200%	200%	All	03LTJ0Y!02	Command Control
05	200%	200%	All	H33!1HFTHK	Phobos Lab
06	200%	200%	All	04MSKZX9Z1	Central Processing
07	125%	200%	All	YTTLCXXLXV	Computer Station
08	200%	200%	All	09SMBY04YW	Phobos Anomaly
09	200%	200%	All	7KKBLD7V53	Diemos Anomaly
10	100%	200%	All	FM4217GSGJ	Containment Area
11	200%	200%	All	H!!3WDGLDB	Refinery
12	200%	200%	All	07QPDW26WY	Deimos Lab
13	350%	150%	12346	WTXQ9C3W12	Command Center
14	100%	200%	123456	RBR4G!LDLN	Halls of the Damned
15	300%	175%	1236	WTXQ9C3W11	Spawning Vats
16	50%	75%	1234567	548C7DFWYX	Hell Gate
17	100%	125%	1234567	JOC89DZPQS	Hell Keep
18	100%	125%	1234567	JGB9CT0NRT	Pandemonium
19	100%	200%	All	9QLTKR0!02	House of Pain
20	100%	200%	All	78M63QX921	Unholy Cathedral
21	200%	200%	All	S!61FHVQJG	Mt. Erebus
22	200%	200%	All	33QHFTT6WY	Limbo
23	200%	200%	All	VBGQPJ!Y46	Tower of Babel
24	200%	200%	All	ZYKTLW7V53	Hell Beneath
25	200%	200%	All	0DJSM4HW64	Perfect Hatred
26	200%	200%	All	LS5YPTCRKH	Sever the Wicked
27	200%	200%	All	ZDJSMVRW64	Unruly Evil
28	200%	200%	All	1YKTX4QV53	Unto the Cruel
29	200%	200%	All	XKF6R8LZ97	Twilight Descends
30	200%	200%	All	DJX07Q4HTR	Threshold of Pain
Doom II
31	200%	200%	All	C0W1!QNJQS	Entryway
32	125%	200%	All	VM!3V1D3DB	Underhalls
33	150%	200%	All	W394W2DMFC	The Gantlet
34	150%	200%	All	ZQ58ZKJRKH	The Focus
35	175%	200%	All	Z758ZKJ8KH	The Waste Tunnels
36	200%	200%	All	5C2V3DQBNL	The Crusher
37	200%	200%	All	NCKBLX7V53	Dead Simple
38	200%	200%	All	1Q580FCRKH	Tricks and Traps
39	100%	200%	All	HTMSKZZ9Z1	The Pit
40	200%	200%	All	WS58ZKCRKH	Refueling Base
41	200%	200%	All	CSNRG2W820	O of Destruction!
42	200%	200%	All	WT670JBQJG	The Factory
43	200%	200%	All	DQLTJ1Y!02	The Inmost Dens
44	100%	200%	All	2N94VFFMFC	The Suburbs
45	200%	200%	All	CQLTJ0Y!02	Tenements
46	200%	200%	All	WR492GDSGJ	The Courtyard
47	200%	200%	All	PFFGXH3777	The Citadel
48	200%	200%	All	JWCJV2X479	Nirvana
49	200%	200%	All	CJJTM35964	The Catacombs
50	200%	200%	All	M!T174XZXV	Barrels of Fun
51	200%	200%	All	5770MX2CDF	Bloodfalls
52	200%	200%	All	YJLW3PPCPM	The Abandoned Mines
53	200%	200%	All	DKKBLM58J3	Monster Condo
54	200%	125%	All	7L3!266DJK	Redemption Denied
Bonus levels
55	200%	200%	All	RCMSKZX9Z1	Fortress of Mystery
56	200%	200%	All	8J94VFHMFC	The Military Base
57	200%	200%	All	RJSMBY04YW	The Marshes
58	200%	200%	All	8K!3WDGLDB	The Mansion
59	200%	200%	All	RKTLCXZ3XV	Club Doom

Playing in linked mode with only one disc:
Note: Sony does not recommend removing a spinning disc from the Playstation.
Connect two Playstations with the linkcable, and power on both systems. Begin Doom on Playstation 1. Select Deathmatch or a cooperative game. Playstation 1 should try to connect to Playstation 2. Wait a few seconds, remove the disc from the Playstation 1, and start the game on Playstation 2. Enter all selections identically to Playstation 1 and begin playing.
The game will hang from time to time. At these points, swap the disc to the other Playstation after waiting a few seconds before removing the disc.