Mostly Unpublished Game Boy Color Cheats ;)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.

  Absoloute X (Prototype)
  Beatmania GB
  Beatmania GB2 - Gotcha Mix
  Beatmania GB - Gotcha Mix 2
  Bomberman Max - Blue Champion (USA), Bomberman Max - Red Challenger (USA), Bomber Man Max - Yami no Senshi (Japan), Bomber Man Max - Hikari no Yuusha (Japan), Bomber Man Max - Ain Version (Japan exclusive release)
  Evel Knievel (USA, Europe)
  Grand Theft Auto 2 (USA, Europe)
  NBA 3 on 3 featuring Kobe Bryant (USA)
  Nakayoshi Cooking Series 1 - Oishii Cake-ya-san
  Rampage - World Tour (USA, Europe)
  Sanrio Timenet - Kako Hen and Mirai Hen

Cheats summary:
generic cheats-8
unique cheats-7
buried secrets-3
fixed generic cheats-1
unverified games-1045
games with secrets-11
games with no secrets found-0
overall progress-~1% done

Absoloute X (Prototype)

(UNI) Stage Skip (added 15.09.20):
At the Stage name screen, press Down + Select + Start to switch to the next stage.

(BUR) Game genie (added 16.09.20):
19C‑EBD‑C42-Replaces the "MIDAS" logo with unused early version of the title screen.

Beatmania GB

(GEN) Secret passwords (added 26.06.2019):
Note, all passwords up to "kobebeef" are unlockable and may be generated by the game. The rest ones aren't generateable so they treated as a secret ones.
Password|bigbeatmix|euro-beat|disco|e.n.k.|classic 3|dj battle
"remix"|+|-|-|-|-|-
"generation"|-|+|-|-|-|-
"visual"|+|+|-|-|-|-
"fever"|-|-|+|-|-|-
"sense"|+|-|+|-|-|-
"world"|-|+|+|-|-|-
"allegro"|+|+|+|-|-|-
"mother"|-|-|+|+|-|-
"passion"|+|-|+|+|-|-
"noisy"|-|+|+|+|-|-
"alterna"|+|+|+|+|-|-
"relaxation"|-|-|+|+|+|-
"silent"|+|-|+|+|+|-
"moonlight"|-|+|+|+|+|-
"kobebeef"|+|+|+|+|+|-
"konami" or
"kcek" or
"beatmania"
|-|-|-|-|-|+
"uuddlrlrba" |+|+|+|+|+|+
Source: gamefaqs.com

(BUR) GameGenie (added 26.06.2019):
011‑75B‑E65-Re-enables unused debug mode. Press Start at the title screen. Only two first options are functional. The second one used for debug "VERSUS" game mode.
081‑79B‑C4E-Use this code with previous one to access another unused debug for testing the gb to gb link connection upon pressing Start at the title screen.
Source: tcrf.net

Beatmania GB2 - Gotcha Mix

(GEN) Secret passwords (added 26.06.2019):
Note, all passwords up to "wonderful" are unlockable and may be generated by the game. The rest one aren't generateable so it treated as a secret one.
"melodious"-Unlock "Friends"
"groovy"-Unlock "Rydeen"
"splendid"-Unlock "Watashiga Obasanni Nattemo"
"supercool"-Unlock "Ultraman no Uta"
"wonderful"-Unlock "Genom Screams"
"yebisusama"-Unlock all above at once.
Source: gamefaqs.com

(BUR) GameGenie (added 26.06.2019):
011‑75B‑E65-Re-enables unused debug mode. Press Start at the title screen. Only two first options are functional. The second one used for debug "VERSUS" game mode.
081‑79B‑C4E-Use this code with previous one to access another unused debug for testing the gb to gb link connection upon pressing Start at the title screen.
Source: tcrf.net

Beatmania GB - Gotcha Mix 2

(GEN) Opposite game modes (added 26.06.2019):
At the game mode screen, put cursor to any mode, hold Select and press A. This will adjust currently selected game mode to be something like "opposite" game mode. For example, another game mode for "NORMAL" is complete hide of the "steps". Opposing mode for "HIDDEN" is "sudden" where "steps" appear near the bottom line instead of hiding there, and so on.
Source: gamefaqs.com

(FIX) Random visuals/animations (added 27.06.2019):
At the Game mode screen, put cursor to "HIDDEN+RANDOM" then hold Start + Select and press A. From now the song visuals/animations will be generated randomly every time you restart a song. This code activates the "opposite" game mode for "HIDDEN+RANDOM" as well, since Select being held.
Source: gamefaqs.com

(GEN) Secret passwords (added 26.06.2019):
Note, all passwords here are unlockable, there are no any secret hidden passwords.
"great"-Unlock "Sunny Day Sunday"
"amazing"-Unlock "Lupin Sansei'78"
"awesome"-Unlock "Truth"
"supreme"-Unlock "Get Wild"
"maximum"-Unlock "Koibito ga Santa Claus"
Source: gamefaqs.com

Bomberman Max - Blue Champion (USA), Bomberman Max - Red Challenger (USA), Bomber Man Max - Yami no Senshi (Japan), Bomber Man Max - Hikari no Yuusha (Japan), Bomber Man Max - Ain Version (Japan exclusive release)

(GEN) Sound test (added 08.05.20):
At the title screen, press Right, Left, Right, Right, Left, Left, Right, Left, Right, Left, Left, Right. A sound will confirm correct code entry. Choose any menu item to get to the Sound test mode.
Source: gamefaqs.com

(UNI) Random Auto Battle mode (added 08.05.20):
At the title screen, if you collected any Charabombs during "Normal game", choose "Battle game", then "Battle" mode. Choose "Strategies", then at the "Battle: Selected" screen, press Up, Down, Select, Start, Down, Up, Start, Select, Up, Down. A sound will confirm correct code entry. Now start a game but instead of waiting for the another player connection via Link mode the battle starts instantly with a randomly selected Charabomb enemy. Both players are CPU controlled, so you can just watch.

Evel Knievel (USA, Europe)

(GEN) Secret passwords (added 09.11.19):
All passwords accepts by the program but there are no indication that they work. You just get the same regular message "INVALID PASSWORD!".
RESET-Resets all extra stages flags.
LEVELS-Unlocks "GRAND FINALE" mode (press Select at the Stage select screen to access it).
LASTSTAGE-Unlocks "SNAKE RIVER CANYON" stage.
Source: gamefaqs.com

Grand Theft Auto 2 (USA, Europe)

(UNI) Credits (added 29.19.29):
Normally, there are no any credits in this game, nor at the demo loop not at the ending. However, wait when the title screen appears for the first time after the game boot, then perform a common for many GB games soft-reset (press A + B + Select + Start). Now after "Tarantula" logo the credits screen will appear.

(UNI) Secret passwords (added 29.19.29):
HOMESWEETHOME-Start at "INDUSTRIAL" area.
JOBSAGOODONE-Start at "RESIDENTAL" area.

NBA 3 on 3 featuring Kobe Bryant (USA)

(UNI) Secret menu (added 05.06.21):
At the Title Menu, press Left, Right, Left, Right, Up, Down, Select. Here you may listen to the sounds and music, view animations and ending credits.

(UNI) Clear CRAM (added 05.06.21):
Enter the "Secret menu" cheat first. Set "ANIM" to 255 and press A.

Nakayoshi Cooking Series 1 - Oishii Cake-ya-san

(GEN) Cart RAM clear (added 16.10.18):
Before powering the console on, hold Up + A + Start then wait until the "MTO" logo appears.

Rampage - World Tour (USA, Europe)

(GEN) 2 Players mode (added 04.02.22):
At the Main menu, hold Select then input Up, Down, Left, Right, Down, Up. A new menu option will appear where you may select players number. But to play with other player you need two Game Boys with two cartridges connected via link cable.
Source: gamefaqs.com

Sanrio Timenet - Kako Hen and Mirai Hen

(UNI) Illusory monsters (added 16.10.18):
There are four secret "Illusory" monsters in this game. You can't fight with them during the game, they only may be added to the Monsters list via secret button codes. To do this, at the title screen, hold Select then input one of the following button sequences. A sound confirms correct code entry. Now just either start a new game or continue the saved game. The only one code may be entered at once. To input another one, save the game and reset the console back to the title screen, input another code and then continue saved game.
Up, Down, Left, Right, Down, Up, Right, Left, Left, Right, Down, Up, Right, Left, Up, Up-Stardust
Up, Down, Left, Right, Down, Up, Right, Left, Left, Right, Down, Up, Right, Left, Up, Left-Planesta
Up, Down, Left, Right, Down, Up, Right, Left, Left, Right, Down, Up, Right, Left, Up, Right-Planetta
Down, Up, Right, Left, Up, Down, Left, Right, Right, Left, Up, Down, Left, Right, Down, Up-Time Surfer

 

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