Mostly Unpublished NES Cheats ;)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.

  Yie Ar Kung-Fu
  Yo! Noid, Kamen no Ninja - Hanamaru
  Yoshi no Cookie, Yoshi's Cookie
  Youkai Douchuuki
  Youkai Club
  Ys
  Ys II - Ancient Ys Vanished - The Final Chapter
  Yuefei (Mars, Union Bond G-006)
  Yu-Gi-Oh (Nanjing, NJ032)
  Yume Penguin Monogatari

Cheats summary:
generic cheats-2
unique cheats-5
buried secrets-8
fixed generic cheats-0
unverified games-0
games with secrets-10
games with no secrets found-9

Yie Ar Kung-Fu

(BUR) Hidden text (added 24.11.08):
There is a hidden version info in ROMs:
RC8021.2 850325
for the 1.2 version and
RC802 1.4 850430
for the 1.4 version.

Yo! Noid, Kamen no Ninja - Hanamaru

All versions:

(BUR) Stage select (added 09.06.14):
The same Stage Select leftovers are present in both versions of this game. At the title screen set RAM var $71 to value $03. There is no code left for proper call of this routine, so it will display right above the garbled title screen graphics. Select a stage number with A or B, toggle invulnerability on and off with Up and Down accondingly. Press Start to play the game. Unfortunately, a stage select isn't working.

Japanese version:

(BUR) Hidden text (added 02.01.09):
There is a hidden copyright info in ROM:
MAAJYAN HIGASHIO NOW PRODUCTION 1988

Source: GDRI

Yoshi no Cookie, Yoshi's Cookie

(GEN) Extra levels:
In the options, turn off the music, set the game to high speed and to Round 10. After that, hold Up and press Select. The Round now will be at "11". Keep pressing Select to make the round go higher.

(BUR) GameGenie (added 31.05.11):
GEUGXXGK (for the Japanese version)
GEUKNXGK (for the US version)
-Re-enables Debug Menu. To enter it, at the title menu, press Down + Right + A + B. You can choose any game parameters to play with, listen to the sound effects and watch all cut scenes, but due to game bug, you can't listen music, "SND" option will hang up the game at all.
AAXLSPAZ+OAXLVPAA+XTXLNPOE (for the Japanese version)
AEUUAIAZ+OEUUPIAA+XVUUZIOE (for the US version)
-Fixes the bug preventing music from playing in debug menu. With these codes you can listen to all music.

Youkai Douchuuki

(UNI) Test mode:
Hold Up + A + B on controller 2 and press Reset.

(UNI) Easter egg (added 28.03.11):
Hold Select on controller 1 and press Reset. The game title "妖怪道中記" ("Youkai Douchuuki" or "Demon Travel Journal") will be changed to "妖艶道中記" ("Youen Douchuuki" or "Erotic Travel Journal").

(BUR) GameGenie (added 28.03.11):
KXESLKNP-Re-enables "SCENE SELECT MODE". To enter it, at the title menu, enter the "CONTINUE" option. Another one "CONTINUE" menu appears with extra option "SCENE SELECT MODE". Enter it and you will be able to select any scene and subscene in game to start.

Youkai Club

(GEN) Continue:
The game has a weird continue/password system. After you beat the level, the code is displayed in the game HUD, which is a cheat sequence you must to enter at the stage display screen in order to continue from the desired level. However, this can be done only for levels 2 and 3. Here is the level codes:
Up, Up, A, Right-Level 2
Up, Left, B, Up-Level 3

(UNI) Debug leftovers (added 28.05.15):
Hold B on controller 2 during the game to aviod some of the collision tests, for example to walk through some wall corners or moving platforms. There are more debug routines left in the game code, but they cause the crash of the game at very beginning if re-enabled.

Ys

(BUR) GameGenie (added 28.05.15):
NNSYEYAE-Re-enables a couple of debug features.
At the title screen, hold A and press Start to enable free walk mode during the game, or hold B and press Start to to obtain 65535 of gold, all items and other stuff. Both codes can be pressed at the same time to combine effects.
During the game hold B and press Select to warp to the next location.
Enter the game menu by press Select, then press Start to instantly increase level.

Ys II - Ancient Ys Vanished - The Final Chapter

(BUR) GameGenie (added 29.05.15):
AAONUNNY+AAONKNNY-Re-enables a couple of debug features.
During the game, press A on controller 2 to toggle the free walk mode on and off.
Press Start on controller 1 to warp to the next location (buggy).
Press Select and enter the stats screen, then press Start on controller 1 to increase current level.

Yuefei (Mars, Union Bond G-006)

(UNI) Easer egg (added 30.01.14):
Start a new game, press Select to enter the main menu. Now press Left + Select + Start on controller 1. A small "MARS" logo will appear at the top-left corner of the screen.

Yu-Gi-Oh (Nanjing, NJ032)

(UNI) Secret message (added 21.05.14):
During the game, while in conversation mode, hold Up + Select + Start on controller 1 and skip with A to the end of the dialog. The copyrigh string will be displayed in the dialog box. This cheat can be found in a couple of Nanjing games on the same engine.

Yume Penguin Monogatari

(BUR) Copyright check (added 05.10.07):
As most of latest Konami games, this one contains some sort of copy protection. At the game start, the program performs a selftest for presence and integrity of the CHR bank with copyright tiles, part of copyright message screen for presence "(c) KONAMI 1991" string, and finally part of code for checking first one string. ;) If tests fails, the game switches to the "hardest" mode. Regular difficulty of the game increased automatically up to value 5. Although the most of difficulty related tests are depends on zero/non zero values, at least one could be affected with a higher values than 5.

 

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