Mostly Unpublished NES Cheats ;)

red    marked cheats are unique, not listed on any site (tell me if not).
brown marked cheats from various other sources like gamefaqs.com etc, checked and fixed if necessary.
gray   marked disabled or missed cheats buried inside game ROM.

  Ochin ni Toshi Puzzle Tonjan!
  Oishinbo
  Olympic IQ (Sachen)
  Operation Secret Storm
  Operation Wolf
  Orb 3D
  Osomatsu-kun
  Over Horizon
  Overlord

Cheats summary:
generic cheats-5
unique cheats-5
buried secrets-6
fixed generic cheats-0
unverified games-0
games with secrets-9
games with no secrets found-7

Ochin ni Toshi Puzzle Tonjan!

(UNI) Music control (added 30.07.14):
During the game, on controller 2, press A to cycle throught the 4 different background melodies, press B to toggle music off and on.

(BUR) Hidden text (added 30.07.14):
There is a hidden copyright text inside the ROM:
COPYRIGHT1989...NIHON MICOM KAIHATSU C1989


Oishinbo

(BUR) GameGenie (added 31.07.14):
AIXSGYTK-Re-enables a picture test feature. During the game, press Select to enable it. Use the D-Pad buttons to select a picture. This catually may crash the programm. Press Start to return back to the game.

Olympic IQ (Sachen)

(UNI) Stage select (added 29.06.13):
At the title screen, press A, B, Up, Down.

Operation Secret Storm

(UNI) Level skip (added 29.06.13):
At the map screen or during the game, hold Up on controller 2 and Up + A on controller 1 then press B on controller 1. This will enable the level skip cheat. Now any time during the game, hold B then press Select on controller 1. Total 12 stages are available, after 12th, you will return back to the stage 1.

Operation Wolf

US version:

(BUR) Debug mode (added 01.08.14):
Set RAM address $009B to any non-zero value to enable a debug leftovers. This will re-enable the stage select with gunsight, gunsight shot display debug (white square). Also you can press Right on controller 2 at the stage select screen to instantly play the extra attack level. During the game press Select on controller 1 to instantly loose the game.

Japanese version:

(UNI) Debug leftovers:
At the title screen, press Up, Down, Right, Left, A, B, Down, Up. This will set the Debug flag, the same as in the US version, but in the Japanese version most of debug features are absent, the only functionality present is a gunsight shot display position debug (white square) at the stage select screen.

Orb 3D

(GEN) Cut fuel consumption by half:
Press A, B, Left, B, A, Right on the intermission screen between levels or before level 1 begins. Fuel use will be at half of normal.

Osomatsu-kun

(BUR) Hidden text (added 29.06.13):
The RESET routine in this game uses string
Yoshikawa
to check if game was soft or hard reset.

(BUR) GameGenie (added 29.06.13):
AESNENNY-Re-enables the simple debug mode. In this mode the password option at the title screen will lead to the stage select screen. To enter the normal password screen, hold B before pressing Start. Additionally, you will have 10000 money at the beginning of the game.

Over Horizon

All versions:

(GEN) Change graphics:
Hold A + B on controller 1 and press Reset. Menu cursor will change to confirm correct code entry.

(UNI) Level skip (added 08.01.08):
Hold Right + A + B on controller 2 and press Reset. While in game, hold Select on controller 1 then by pressing A on controller 2 advance to the next level.

Japanese version:

(GEN) Sound test:
Hold Up + Select + Start on controller 1 and press Reset. There is no such cheat in the European version.

(BUR) GameGenie:
ITXIAVTT-Enable unused game scene, seems used to be some alternative ending scene draft. Just press Start at the title screen to see it instead of the game start.

Overlord

(GEN) Extra credits:
At the title screen, or at the "Virgin" logo, press any button except Start to enable an extra credits screen with "Probe" logo and main staff names and pictures.

(GEN) Intro skip:
Before starting a new game, hold Left. This will skip the intro messages.

 

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