Dragon Quest Monsters: Joker/ROM map

The following article is a ROM map for Dragon Quest Monsters: Joker.

Filesystem

• data - Data files that the game reads information from (ex. images, tables, etc.).
• overlay - Overlay binary files.
  • overlay_0000.bin - Overlay for the overworld.
  • overlay_0001.bin - Overlay for battles.
  • overlay_0002.bin - Overlay for currently unknown purpose.

File Formats

FPK Package Files

The game stores some files together into one package file. These package files have a file extension of ".bin" and begin with the magic letters "FPK".

struct file {
    u8 name_info[0x20];
    u32 offset;
    u32 size;
    u8 data[size] @ offset;
};

struct fpk {
    u32 magic;
    u32 num_files;
    file files[num_files];  
};

fpk fpk @ 0x0;

d16 Image Files

The game stores cutscene image files in the binary "d16" file format. Values are stored as little endian.

u32 magic @ 0x00; // "D16 " (44 31 36 00)
u16 width @ 0x04;
u16 height @ 0x06;

u16 pixels[width * height] @ 0x08; // 16bit colors, 0b1BBBBBGGGGGRRRRR

Event Files

The game stores events as binary files in the custom ".evt" file format. Event files consist of a data portion and an instructions portion.

Instructions are executed one by one in order. Instruction 0x0A will initiate a new separate thread of execution, which runs concurrently, but not in parallel, with the main execution thread of the event.

#include "std/mem.pat"

u32 magic @ 0x00;
u8 data[0x1000] @ 0x04;

struct instruction {
    u32 type;
    u32 length;
    u8 arguments[length - 8];
};

// Instruction from end of data section to end of file
instruction instructions[while(!std::mem::eof())] @ 0x1004;

In the European release of the game, many event files are stored as FPK package files. The package files contain 5 event files, one for each language the game supports:

• ".evD" - German
• ".evE" - English
• ".evF" - French
• ".evI" - Italian
• ".evS" - Spanish

Binary files

Dir	Name	File extension	Category	Description
./	arm7.bin	bin	Exectuable
./	arm9.bin	bin	Exectuable	The exectuable with most of the game's code.
./	banner.bin	bin
./	header.bin	bin
./	y7.bin	bin
./	y9.bin	bin
overlay	overlay_0000.bin	bin	Exectuable
overlay	overlay_0001.bin	bin	Exectuable
overlay	overlay_0002.bin	bin	Exectuable
data	AI_ActionTBL.bin	bin
data	AI_CorrectTbl.bin	bin
data	AI_IntelTBL.bin	bin
data	AI_PatternTbl.bin	bin
data	AI_TargetSelectAllyTbl.bin	bin
data	AI_TargetSelectEnemyTbl.bin	bin
data	AI_TargetSelectItemTbl.bin	bin
data	AbilityTbl.bin	bin	Data table	Table of stat increase per-level categories
data	BtlChrTbl.bin	bin
data	BtlChrTimeTbl.bin	bin
data	BtlEfcTbl.bin	bin
data	BtlEfcTblWhip.bin	bin
data	BtlEnmyPrm.bin	bin	Data table	Table of special encounter monsters (ex. bosses)
data	BtlMstrPrm.bin	bin
data	ChgContentTbl.bin	bin
data	ChgMnstrTbl.bin	bin
data	DamageItemTbl.bin	bin
data	DamageTbl.bin	bin
data	DemoChrTbl.bin	bin
data	EnmyKindTbl.bin	bin	Data table	Table of monster species
data	EnmyPtnTbl.bin	bin
data	ExperienceTbl.bin	bin
data	FldChrTbl.bin	bin
data	FldEnmyPrm.bin	bin
data	FldMstrPrm.bin	bin
data	ItemTbl.bin	bin	Data table	Table of items and equipment
data	ModelTbl.bin	bin
data	MotionTbl.bin	bin
data	MstrPtnTbl.bin	bin
data	SkillPointTbl.bin	bin
data	SkillTbl.bin	bin	Data table	Table of skill sets
data	TokugiDataTbl.bin	bin
data	ViewChrTbl.bin	bin
data	btl_data.bin	bin
data	console_data.bin	bin
data	field_data.bin	bin
data	infomation_data.bin	bin
data	island_data.bin	bin
data	joker_00.bin	bin
data	keybord_data.bin	bin
data	omiaitbl.bin	bin
data	sd_data.bin	bin
data	shop_data.bin	bin
data	shop_vram.bin	bin
data	start_data.bin	bin
data	status_data.bin	bin
data	wall_bank.bin	bin
data	wall_base.bin	bin
data	wall_combi.bin	bin
data	wall_gpinfo.bin	bin
data	wall_itemshop.bin	bin
data	wall_keep.bin	bin
data	wall_skillpoint.bin	bin

AbilityTbl.bin

The ability table stores level-up stat increase patterns, which determine how many stat points a monster will get when leveling up. Each pattern includes 99 unsigned integers which represent stat value increases for each level (1-99). There are 32 different patterns in total.

Each monster species is given 24 stat increase patterns. 6 groups corresponding to the different monster stats: max hp, max mp, attack, defense, agility, and wisdom. Each of the six groups has 4 patterns which apply to different level ranges: level 1 to 9, 10 to 39, 40 to 50, and 51 to 99.

struct ability {
    // One byte for each level
    u8 increase[99];
};

struct AbilityTbl {
    ability abilities[32];
};

AbilityTbl table @ 0x0;

EnmyKindTbl.bin

The enemy kind table stores information on the different monster species, such as default stats, stat limits, and stat increase pattern ids.

struct species {
    u32 unknown_a;
    
    u8 rank_and_family; // Lower 4 bits are the rank (0x0F), higher 4 bits are the family (0xF0)

    u8 unkown_b[3];
    u8 unknown_c[4];
    
    u32 weapon_compatibility_and_something_else;
    u8 traits[5];
    
    u8 unknown_d[3];
    u8 unknown_dde[4];
    
    u8 default_max_hp;
    u8 default_max_mp;
    u8 default_attack;
    u8 default_defense;
    u8 default_agility;
    u8 default_wisdom;
    
    u8 unknown_de[2];
    
    u16 max_hp_limit;
    u16 max_mp_limit;
    u16 attack_limit;
    u16 defense_limit;
    u16 agility_limit;
    u16 wisdom_limit;
    
    u8 max_hp_increase_indicies[4];
    u8 max_mp_increase_indicies[4];
    u8 attack_increase_indicies[4];
    u8 defense_increase_indicies[4];
    u8 agility_increase_indicies[4];
    u8 wisdom_increase_indicies[4];
    
    u8 skill_set;

    u8 unknown[75];
};

struct enmy_kind_tbl {
    u32 magic;
    u32 size;
    species species[size];
};

enmy_kind_tbl enmy_kind_tbl @ 0x0;