Quake 2

Debug menu:
Enter QQQQ QQQQ QQQQ QQQQ as a password. The sound of a roar will confirm correct code entry. The "Debug" option will now appear at the main menu and paused game menu. The debug options include "God Mode", "All Weapons", "Level Select" and more.

Twists level:
Enter FBBC VBBB FBBC VBF7 as a password. This is deathmatch level with a 1:40 time limit and rocket launcher. Enter FLBC ZBBB FLBC ZBB9 to play the level under the medium difficulty setting or FVBS LBBB 7VBC 3BB5 to play under the hard difficulty setting.
Information in this section was contributed by David Couch.

Additional costume colors:
Enter S3TC 00LC 0L0R S??? as a password.
Information in this section was contributed by poky1.

Low gravity in multi-player mode:
Enter S3TL 0WGR V1TY ???? as a password.
Information in this section was contributed by David Couch.

All weapons:
Enter 6522 BHFV TBNA Z1BC as a password.

Unlimited ammunition in multi-player mode:
Enter S3T1 NF1N 1T3S H0TS as a password. Note: This code also allows higher jumps.
Information in this section was contributed by JVGART5 and poky1.

End level:
Enter F60? VQCH ?BHF DQQL as a password.

Level 31:
Select Viper as a player. Rename the player Ozz. Play through the first four missions to get the password to mission 31. The password is 1HLN 3LVC 04BT DBSV.
Information in this section was contributed by Matt Crews.

Level	Name	Password
Easy
1	Central Complex	(none)
2	Intelligence Center	6JBN SHFB 07BR X3J1
3	Communications Center	1KLG VL2H LNBF F4LQ
4	Orbital Defense	2KQD 2MSD Z9VM 4XYL
5	Docking Station	VK7N Z?LY ?4V5 LJ4W
6	Strogg Freighter	VK3J HSW5 9GZN LQW9
7	Cargo Bay	TK3T RN5N Q06W JV05
8	Zaxite Mines	S?WM H1G9 B46C WBOD
9	Storage Facility	R8WB 8X7J VGQ0 SJWR
10	Organic Storage	Q?WB BLW8 RP6Y XLSN
11	Processing Center	P6P5 KYWX HB8R DJZH
12	Geothermal Station	N520 KJFW Y681 VLMD
13	Detention Center	M525 TZ35 HXW0 BXZ8
14	Research Lab	L56X 41DX ZKR8 VJV8
15	Bio-Waste Treatment	K58V 01HJ V5K9 C3VK
16	Access Conduits	J584 W6NR D05B VDQ?
17	Descent to Core	H522 98MJ SM1C B82C
18	Command Core	G52W 300Z 561C W4HK
19	Final	F569 G2D6 HT6X SG5Y
Normal
1	Central Complex	(none)
2	Intelligence Center	PGBR VK?B 65BH Y3HD
3	Communications Center	1KLS DN5H 7NBF DWRQ
4	Orbital Defense	2KLR SDRY ?VV4 YQ8X
5	Docking Station	VK3T 7LFC 94B7 D3R3
6	Strogg Freighter	WK3H QNBW NLV5 XGL3
7	Cargo Bay	TK7P 6LLP KWGY XD4V
8	Zaxite Mines	ST0N QPX4 2WGY JXTS
9	Storage Facility	R??P 7NY4 2WGX 99TX
10	Organic Storage	Q??K BBBV NBQ1 7GCV
11	Processing Center	P64? ZM5B ?BM0 5YH6
12	Geothermal Station	N664 SQ63 XB?K B7LF
13	Detention Center	M682 M7QT 1215 8098
14	Research Lab	L669 H8MD G8XB JNYV
15	Bio-Waste Treatment	K681 X8CL H01K 1PF5
16	Access Conduits	J6?0 BT5M NRZ2 QXLL
17	Descent to Core	H6?0 XXFW PHV1 77P4
18	Command Core	G6?9 GYMK RWNK SMSL
19	Final	F6Y3 WXQK CHD0 8K4D

Some information in this section was contributed by poky1.