Mega Man Battle Network 4.5 is the one Battle Network game which never got an official translation. This means the game is only available in Japanese. However, there is a patch which aims to match an official translation. In this game, you can play as over 20 different Navis in Operation Battle mode.
To follow this guide, you need VisualBoyAdvance (VBA) and a backup of the game. I do not condone piracy, but if you somehow already have a copy, follow along.
This game has freefights, but because they are all time-specific and require unlocking, it’s easier to go for the random encounters in Internet 1.
Download Battle Network 4.5 saves.
Here is where you should be. It’s just the first Internet area.
Using VBA’s Memory Viewer window, the following steps will let you make temporary changes. Remember that any changes will be lost if the emulator is closed. You can make the changes permanent if the same steps are done in a hex editor such as HxD.
To make your own battle, a battle will first have to be made in free space. On an unpatched game, freespace begins at the following offset.
087D3E10
If the space isn’t free, simply find freespace and move on to the next step.
This free space will be used to enter the battle data needed for your battle. First, you write the Battle Settings data. Enter the following default data to get started.
20 00 28 62 00 FF 1F 00 55 8E 0C 08
The format is documented below.
0x00 Encounter Type
0x01 Battlefield
0x02 Unknown
0x03 Music
0x04 Battle Mode
0x05 Background
0x06 Enemy Level/Effect
0x07 Battle Number Count
0x08 Object Setup Pointer (4 bytes)
When you’ve decided on the free space, write that pointer to the following offset.
080C7C34
It should be written in reverse if you are looking at it in 8-bit view. 087D3E10 would become 10 3E 7D 08.
0x00 Encounter Type
This value affects how the battle is encountered. If the value is 20, then you can encounter it.
Default is: 20
0x01 Battlefield
This byte lets you choose from the game’s 148 premade battlefields. Each stage has a different arrangement of panel types. The stages are the same as in MMBN4.
Default is: 00
0x02 Unknown
It is unknown what this value does.
Default is: 28
0x03 Music
This game finally lets you change the music through the Battle Settings. The value of 14 means its using the Virus Battle Theme. The full music list is below.
Default is: 62
00 = No Music
09 = Tournament Selection
0E = Transmission
18 = Winner Theme
19 = Loser Theme
1A = Game Over
1B = Boss Prelude
1E = Winner Theme (short version)
1F = Tournament Winner
28 = Theme of WindMan
29 = Theme of GutsMan
2A = Theme of FireMan
2B = Theme of ElecMan
2C = Theme of MetalMan
2D = Theme of WoodMan
2E = Theme of IceMan
2F = Theme of ShadowMan
30 = Theme of StarMan
31 = Theme of NapalmMan
32 = Theme of KnightMan
33 = Theme of PlantMan
34 = Theme of JunkMan
35 = Theme of Bass
36 = Theme of ProtoMan
37 = Title Screen
38 = Navi Select
39 = MetalMan Mini-Game
3A = Mini-Game Explanation
3B = WindMan Mini-Game
3C = Tournament Mini-Battle
3D = NapalmMan Mini-Game
3E = IceMan Mini-Game
3F = Official Tournament Winner
40 = Internet Theme
41 = Undernet Theme
42 = Chaos Area Theme
43 = Credits Theme
44 = Intro PET Sound
59 = Tournament Battle
5A = Theme of MegaMan
5B = Theme of AquaMan
5C = Theme of SearchMan
5D = Theme of Roll
5E = Theme of NumberMan
5F = Theme of ThunderMan
60 = NumberMan Mini-Game
61 = SearchMan Mini-Game
62 = Virus Battle
63 = Boss Battle
0x04 Battle Mode
Battle Mode lets you play special battles like tutorials or ending the battle with no results. The full list of battle modes are below.
Default is: 00
00 = Normal Battle
04 = Disable Game Over
10 = No Running Battle
20 = Start Battle with Max HP
40 = Battle Tutorial
44 = Free Tournament Mode
45 = No Results
Some notes:
Though the previous game’s tutorial battles were removed, you still get the folders associated with them.
Free Tournament Mode has been broken and covers up your custom gauge. You can still skip the battle with Select.
0x05 Background
This byte lets you change the background for the battle. This game has all the backgrounds from MMBN4 and backgrounds exclusive to the game. The full background list is below.
Default is: FF
00 = ElecTownTower BG
01 = ToyRobo Comp BG
02 = Lan's HP BG
03 = Generic Comp BG
04 = ACDC Area BG
05 = Town Area BG
06 = Park Area BG
07 = YumLand Area BG
08 = Undernet Area BG
09 = Dark Generic Comp BG
0A = Meteor Comp BG
0B = Mayl's HP BG
0C = Dex's HP BG
0D = Yai's HP BG
0E = Hotel BG
0F = Castillo BG
10 = JomonElec HP BG
11 = Black Earth BG
12 = Dracky Comp BG
13 = Netopia Area BG
14 = Netfrica Area BG
15 = Sharo Area BG
16 = Space Center BG
17 = Duo Battle BG
18 = Green Tournament BG
19 = Blue Tournament BG
1A = Gold Tournament BG
1B = Internet1-3 BG
1C = Internet4-7 BG
1D = Internet7-9 BG
1E = Undernet BG
1F = Undernet BG
20 = Green Regular BG
21 = Blue Regular BG
22 = Yellow Regular BG
FF = Inherited from Map
0x06 Battle Effects
Battle effects modify other aspects of the battle which can even get the tournament intro to appear during battle, which this game doesn’t normally use. The full battle effects table is listed below.
Default is: 1F
1 = Battle can be encountered
2 = Unknown
4 = Unknown
8 = Unknown
10 = Unknown
20 = Tournament Intro
40 = Multiplayer Mode
80 = Force Lower Level
Effects can be combined using Windows Calculator. Two effects can be added together to get both effects.
Value 40 for Multiplayer Mode has no apparent effect.
For 80, forcing lower level is necessary to fight all versions of enemies.
0x07 Battle Number Count
For values above 00, the number of the battle appears after the viruses appear. This is normally reserved for sequential battles.
Default is: 00
0x08 Object Setup Pointer
This is the pointer to the object setup data which details where the player and enemies appear. If you copied the default values from above, it should be pointing to the old battle in Internet 1.
Overwrite these 4 bytes to 20 3E 7D 08 or +10 in hex from wherever your base offset is. This will be necessary for the next step.
When you’ve set all the Battle Settings, you can start writing the Object Setup data. Using the above offset, go to the following offset.
087D3E20
To read and write the Object Setup format, follow the documentation below.
0x00 Enemy Value
0x01 X-Position
0x02 Y-Position
0x03 Object Type
Every object requires these 4 bytes to fill one “slot”. Each slot can contain an object, an enemy, or the player. The game stops reading when the enemy value is FF which is after the last object type. More unfortunate in this game, only 3 enemies are supported on the battlefield at once. The 4th enemy will slow down the custom screen considerably. The game could also freeze when any enemy attacks. The 4th name however, appears fine. 3 Navis on the battlefield also make the game unstable.
0x00 Enemy Value
This value determines which enemy you encounter. This value also acts as the Flag’s HP when it is being used in that slot. The full enemy list is below.
00 = MegaMan
01 = Mettaur
02 = Mettaur EX
03 = Mettaur2
04 = Mettaur2 EX
05 = Mettaur3
06 = Mettaur3 EX
07 = VolGear
08 = VolGear EX
09 = VolGear2
0A = VolGear2 EX
0B = VolGear3
0C = VolGear3 EX
0D = Billy
0E = Billy EX
0F = Silly
10 = Silly EX
11 = Killy
12 = Killy EX
13 = Gaia
14 = Gaia EX
15 = Gaia +
16 = Gaia + EX
17 = GaiaMega
18 = GaiaMega EX
19 = Spikey
1A = Spkiey EX
1B = Spikey2
1C = Spikey2 EX
1D = Spikey3
1E = Spikey3 EX
1F = Shrimpy
20 = Shrimpy EX
21 = Shrimpy2
22 = Shrimpy2 EX
23 = Shrimpy3
24 = Shrimpy3 EX
25 = Boomer
26 = Boomer EX
27 = Gloomer
28 = Gloomer EX
29 = Doomer
2A = Doomer EX
2B = Trumpy
2C = Tuby
2D = Tromby
2E = MuteAnt
2F = Xylos
30 = Trumpy EX
31 = MagTect
32 = MagTect EX
33 = MagTect +
34 = MagTect + EX
35 = MagTectX
36 = MagTectX EX
37 = Melody
38 = Melody EX
39 = Hellody
3A = Hellody EX
3B = Felony
3C = Felony EX
3D = Dharma
3E = Dharma EX
3F = Karma
40 = Karma EX
41 = Dogma
42 = Dogma EX
43 = Kilby
44 = Kilby EX
45 = Kilbur
46 = Kilbur EX
47 = Kilbo
48 = Kilbo EX
49 = Weather
4A = Whomper
4B = Winger
4C = Wonder
4D = Wither
4E = Weather SP
4F = Spidy
50 = Spidy EX
51 = Webby
52 = Webby EX
53 = Arachy
54 = Arachy EX
55 = Lark
56 = Lark EX
57 = Bark
58 = Bark EX
59 = Tark
5A = Takr EX
5B = CirKill
5C = CirKill EX
5D = CirCrush
5E = CirCrush EX
5F = CirSmash
60 = CirSmash EX
61 = Moloko
62 = Moloko EX
63 = Milko
64 = Milko EX
65 = Macko
66 = Macko EX
67 = Walla
68 = Walla EX
69 = Walland
6A = Walland EX
6B = Waldon
6C = Waldon EX
6D = Elemperor1
6E = Elemperor2
6F = Elemperor3
70 = Elemperor4
71 = Elemperor5
72 = Elemperor SP
73 = BombBoy
74 = BombBoy EX
75 = BombWorker
76 = BombWorker EX
77 = BombLaboror
78 = BombLaboror EX
79 = WindBox
7A = VaccuumFan
7B = WindBox2
7C = VaccuumFan2
7D = WindBox3
7E = VaccuumFan3
7F = Nothing
80 = Roll
81 = Roll Alpha
82 = Roll Beta
83 = Roll Omega
84 = GutsMan
85 = GutsMan Alpha
86 = GutsMan Beta
87 = GutsMan Omega
88 = WindMan
89 = WindMan Alpha
8A = WindMan Beta
8B = WindMan Omega
8C = SearchMan
8D = SearchMan Alpha
8E = SearchMan Beta
8F = SearchMan Omega
90 = FireMan
91 = FireMan Alpha
92 = FireMan Beta
93 = FireMan Omega
94 = ThunderMan
95 = ThunderMan Alpha
96 = ThunderMan Beta
97 = ThunderMan Omega
98 = ProtoMan
99 = ProtoMan Alpha
9A = ProtoMan Beta
9B = ProtoMan Omega
9C = NumberMan
9D = NumberMan Alpha
9E = NumberMan Beta
9F = NumberMan Omega
A0 = MetalMan
A1 = MetalMan Alpha
A2 = MetalMan Beta
A3 = MetalMan Omega
A4 = JunkMan
A5 = JunkMan Alpha
A6 = JunkMan Beta
A7 = JunkMan Omega
A8 = AquaMan
A9 = AquaMan Alpha
AA = AquaMan Beta
AB = AquaMan Omega
AC = WoodMan
AD = WoodMan Alpha
AE = WoodMan Beta
AF = WoodMan Omega
B0 = TopMan
B1 = TopMan Alpha
B2 = TopMan Beta
B3 = TopMan Omega
B4 = ShadeMan
B5 = ShadeMan Alpha
B6 = ShadeMan Beta
B7 = ShadeMan Omega
B8 = BurnMan
B9 = BurnMan Alpha
BA = BurnMan Beta
BB = BurnMan Omega
BC = ColdMan
BD = ColdMan Alpha
BE = ColdMan Beta
BF = ColdMan Omega
C0 = SparkMan
C1 = SparkMan Alpha
C2 = SparkMan Beta
C3 = SparkMan Omega
C4 = KnightMan
C5 = KnightMan Alpha
C6 = KnightMan Beta
C7 = KnightMan Omega
C8 = NormalNavi
C9 = NormalNavi Alpha
CA = NormalNavi Beta
CB = NormalNavi Omega
CC = HeelNavi
CD = HeelNavi Alpha
CE = HeelNavi Beta
CF = HeelNavi Omega
D0 = LaserMan
D1 = LaserMan Alpha
D2 = LaserMan Beta
D3 = LaserMan Omega
D4 = KendoMan
D5 = KendoMan Alpha
D6 = KendoMan Beta
D7 = KendoMan Omega
D8 = VideoMan
D9 = VideoMan Alpha
DA = VideoMan Beta
DB = VideoMan Omega
DC = NaviShadow
DD = NaviShadow Omega
DE = NaviBlack
DF = NaviBlack Omega
E0 = NapalmMan
E1 = NapalmMan Alpha
E2 = NapalmMan Beta
E3 = NapalmMan Omega
E4 = Bass
E5 = Bass Omega
E6 = Bass XX
E7 = Bass Omega
E8 = StarMan
E9 = StarMan Alpha
EA = StarMan Beta
EB = StarMan Omega
EC = ShadowMan
ED = ShadowMan Alpha
EE = ShadowMan Beta
EF = ShadowMan Omega
F0 = IceMan
F1 = IceMan Alpha
F2 = IceMan Beta
F3 = IceMan Omega
F4 = PlantMan
F5 = PlantMan Alpha
F6 = PlantMan Beta
F7 = PlantMan Omega
F8 = ElecMan
F9 = ElecMan Alpha
FA = ElecMan Beta
FB = ElecMan Omega
FC = Bass
FD = Bass Alpha
FE = Bass Beta
FF = Bass Omega
Some notes:
Bass has a few extra versions the other Navis don’t have. E5 is the same as E7. At the bottom of the list, Bass has versions in the same style as the other freefightable Navis. However, Bass doesn’t follow this pattern and values FC-FF show up as Mettaurs that drop WoodMan chips.
0x01 X-Position
The second byte specifies the X-position of the object. Values represent whole panels on rows. Use the table below.
[01][02][03][04][05][06]
0x02 Y-Position
This byte determines the object’s Y-position. Values represent whole panels on columns. Use the table below.
[01]
[02]
[03]
0x03 Object Type
This byte determines the kind of enemy or object that fills the slot. Actual objects like Rocks don’t count against the maximum enemy limit. Below is a full list of object types.
00 = Player-Controlled Navi
01 = Enemy
02 = Mystery Data
03 = Rock
04 = Nothing
05 = Metal Gear
06 = Nothing
07 = Nothing
08 = Fight on Red Side
Some notes:
Player-Controlled Navi is whatever Navi you are playing as. You can’t change who to play as through here.
Mystery Data doesn’t normally appear in this game. As a result, you won’t get any data after battle for it. Your Navi also can’t target it.
DS Navis were removed in this game and it isn’t possible to fight them through value 04 like in MMBN4.
When value 08 is used, the enemy can fight on the red side with MegaMan. Most viruses and Navis play with little problem. The enemy’s HP becomes the player’s HP which is shared, making it easy to lose, fast.
And that concludes the MegaMan Battle Network 4.5 Custom Battle Guide! Check to see if your battle is loading and make sure you followed every step carefully.
Here is a sample video demonstrating what this guide lets you do!