Version 0.02 has been released!

Here is the official release from PureSabe: http://www.geocities.jp/borokobo/zip/Rock4mi_002_2.zip

This updated version includes an extensive configuration menu, including Hard Mode and some other difficulty options. It also contains the secret fight from the leaked patch a few months ago, a speedrun mode, and a few more minor changes.

0.02 is the latest and greatest version of the patch, officially released or otherwise, as of this writing.


Rockman 4 Minus Infinity(Rockman 4-∞, ロックマン4-∞, ロックマン フォー マイナス 無限大)is an excellent Mega Man 4 ROM hack by Japanese ROM hacker Puresabe (ぷれさべー).

An archive containing a pre-patched ROM of the latest version of the game is here: http://www.mediafire.com/download/qq2kqcbkinq3kqb

If you wish to patch it yourself, the relevant links and directions are below.
The 0.02 patch is here: http://www.geocities.jp/borokobo/zip/Rock4mi_002_2.zip
PureSabe's website is here: http://borokobo.web.fc2.com/index.html


To patch version 0.02:
1. Find a clean Japanese Rockman 4 ROM and save it to your computer.
2. Download and unzip the Rockman 4MI 0.02 patch.
3. Run R4MIPatch.exe. From there, locate the Rockman 4 ROM.
4. Two console windows will open up. They will spew a dozen or so lines of badly formatted Japanese (assuming your computer's locale isn't Japanese). When they are done, press "Enter" in each of them to dismiss it.
5. You should find two new files, rockman4_mi_MMC5.nes and rockman4_mi_MMC5.nes. These are the patched ROMs.


Q: Who are you and what is this website?
I am someone who played and enjoyed this game, but I had trouble finding information about it. I want to encourage people to play this game and share the fruits of my research, but I am not an experienced web designer, so forgive the minimalist aesthetic.

I own nothing on this website. Please feel free to distribute the information contained within to your heart's content. If you want to distribute the archive, you have my permission, but remember that Mega Man 4 is owned by Capcom and Rockman 4 MI is owned by PureSabe.

Q: Is this game complete?
A: It seems to be mostly complete, though there are a few things missing. There are bonus points in the results screen that are still unaccounted for, and Special Mode has not yet been completed. The files and information in this package are current as of July 20, 2013.

Q: What makes this game so great?
A: It is a masterwork in terms of game design and ROM hacking. All of the weapons are powerful and fill different niches. There's at least one or two impressive new features on each level, and they're integrated into the game well. It hits the challenge sweet spot; it's more challenging than Mega Man 4, but without relying on artificial difficulty. It does not expect you to use save states or be some kind of ROM hack savant. I would compare it to Brutal Mario, if you have played that. Many of the bosses change their pattern when they go critical. They also have change their behavior when you equip the Rush Cannon. It works a few short comical scenes seamlessly into its levels. References to other games are frequently worked in as well.

Q: What are the configuration settings.
You can set the language to either Japanese or Engrish. The author promises to offer an English option soon.
You can select a "preset" difficulty mode that sets all of the fields below. There's Easy, Normal, and Hard, as well as "Fixed" mode that is like Normal but turns off the random elements, critical hits and item drops.
"Main" is the main difficulty setting. There are many differences between Normal and Hard Mode; too many to list.
"Damage" affects how much damage Mega Man takes. 1.0 is the default. Setting it to 0.5 makes the game easier, as you take half as much damage. 1.5 makes it harder.
"Critical" is whether Mega Man performs random critical hits or not.
"Item Drop" affects how often enemies drop powerups.
"Fail-Safe" starts you with the Trampoline and Shock Guard items.
"E.Gen." affects whether you start with the "Energy Charger" item.
You can also change how much life Mega Man has (from 1 all the way to the default 28, useful for making the game harder or enforcing a Mr. Perfect run), how many lives he has, and how many E-Tanks he starts with.

Q: What features does this game have?
This game supports battery save, so no fussing around with save states or passwords.
You can switch weapons on the fly by pressing B and A on the second controller. If you are playing on an emulator, it is recommended that you map these buttons to convenient locations: say, L and R on your gamepad.
Rarely, once in about every 100 attacks or so, you will score a critical hit. There will be a flash and a sound effect, and the enemy will take severe damage.
The Rush Coil has been replaced by the Rush Search, which produces large health pellets, large energy pellets, 1-Ups, and E-Tanks. The other Rush vehicles have been replaced as well.
You begin the game with three items. The first is the Energy Balancer, which functions as in Mega Man 6 and beyond.
The second is the Energy Charger, which partially fills up all of your weapon energy when you die. It is useful so that you don't get screwed when you run out of a boss's weakness and die. The challenge is great enough that you will be glad you have it.
The third is the Exchanger, which converts excess health into weapon energy.

Q: Isn't there a version 0.05 out there? Where can I find it?
No, there isn't. 0.02 is the latest and greatest version of the patch.
There was a leaked patch between 0.01 and 0.02 that was unofficially called "005kurai", but it is older than and inferior to version 0.02. 
The version number is a lie. It is not really version 0.05. It is not newer or better than 0.02.
Yes, it's confusing. I agree.
If I haven't succeeded in deterring you from wanting to play this old, obsolete version of the patch, here you go.
Please don't spread that version of the patch around or cause confusion about which version of the patch is newest.

Q: Can the game be run on hardware?
A: Yes. Please check out this thread: http://www.romhacking.net/forum/index.php?topic=15040.0