Proto:Pokémon Yellow

This page details one or more prototype versions of Pokémon Yellow.

This page or section details content from the March 2020 Nintendo Leak (AKA: "Gigaleak"). Check the March 2020 Nintendo Leak category for more pages also sourced from this material.

A debug build was included in pack_nopass.zip from the Wack0 leaks with the filename "YELLMONS.GBC". The build is based off the final English release of the game.

This needs some investigation. Discuss ideas and findings on the talk page. Specifically: Other late-prototype English builds exist with an unknown number of differences, also from the Wack0 leaks.

Debug Features

On the title screen, press Select to be brought to a rather bare-bones debug menu with the options "Fight" and "Debug". The former option lets you set up a Pokémon battle. The latter starts the game off with debug settings.

Regardless of whether you begin a normal game or begin one through the debug option, there are teleports in the right wall of your bedroom that take you to various Team Rocket encounters.

Fight Option

This screen lets you select your party. You can control what Pokémon you have and their levels. Press Start to confirm your team.

This lets you toggle what Pokémon to fight against. There's an option at the top which toggles between the Pokémon you're up against and trainer class. The rival's default name is "Juerry", a potential misspelling of "Jerry". Additionally, the player's name is "Tom" in battle, making the intended reference obvious.

Debug Option

• Starts you off in front of your house.
• Gives you a complete Pokédex.
• Gives you the debug party found in the final game.
• Lets you disable wild encounters and trainer encounters by holding B.
• Interacting with Pikachu while in your bedroom cycles through his expressions.
• Interacting with the Pallet Town sign will instead say "240bit" (or "２４０ビット" in the Japanese version). The "bit" is of unknown significance, but the "240" comes from wWhichPewterGuy (pret naming)/"temp_box_s" ("official" naming):

kan2:
  ifn	pm_debug
	db	CALL_MSG

	ld	a,<VanishBottom
	inc	a
	ld	(temp_box_s),a

	ld	hl,kan1_0$
	call	put_win_msg

	jp	msg_return


kan1_0$:
	db	N_MSG
	dw	temp_box_s
	db	013h				; 1 = byte 3 = ketasuu
	db	D_MSG
   ifn	pm_jmsg
	db	bi__,ttu__,to__
   else
	db	usf_b_,usf_i_,usf_t_
   endif
	db	EOMeom
  else
	extern	kan1_0_7_TOWN01
	db I_MSG2	; mvmsg追加
	dw kan1_0_7_TOWN01	; mvmsg追加
	db 02dh	; mvmsg追加
	db EOM	; put_msg_s終了コード mvmsg追加
  endif