Q: What is this?
This is Rockman 4 Minus Infinity by PureSabe, an exceedingly good ROM hack
of Mega Man 4. (Disclaimer: I am not associated with PureSabe.)

Q: What's in this archive?
It contains the following:
- The pre-patched ROMs.
- The creator's official release of the Rockman4MI patch, which contains the
  patching software, a Japanese readme, a few other Japanese documents about
  the game, and a very brief English readme.
- The clean Japanese Rockman 4 ROM.
- This readme.

Q: How do I patch it?
As this package contains both pre-patched ROMs, there is no need. 
However, for reference:
1. Find a clean Japanese Rockman 4 ROM and save it to your computer. 
   (As included herein.)
2. Download and unzip the 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. When they are done, press "Enter" in each one to 
   dismiss it.
5. You should find two new files, rockman4_mi_MMC3.nes and 
   rockman4_mi_MMC5.nes.

Q: What's the difference between the MMC3 and MMC5 versions?
The MMC5 version is technically superior. There is less slowdown and the 
charging sound doesn't interrupt the music.
The author guarantees that the MMC5 version will work in FCEUX and that the 
MMC3 version will work in VirtuaNes. Other emulators may have issues, ranging
from minor visual bugs to completely not working.
Go ahead and try either version in your preferred emulator, but I personally
recommend just playing the MMC5 version in FCEUX.
MMC3 and MMC5 are chips that NES cartridges contained. The MMC5 is a later, 
more advanced chip. Mega Man 4 was originally made for the MMC3 chip, but
PureSabe ported it to the MMC5 chip for his romhack to take advantage of its 
more advanced capabilities.

Q: How do I start the game?
Press Start and A together on the title screen. I'm not sure why PureSabe did
this. Starting a new game does erase your save data, so I suppose it is a 
measure to prevent players from doing that by accident.

Q: Is this game complete?
Yes! Although, as PureSabe's English Readme states, the game may be updated in
the future if a major bug is found, or the guy who was offering to help him 
with the English translation ever gets back to him.

Q: Where can I find the latest version of Rockman 4 MI?
PureSabe's website is difficult to find with Google. 
It is here: http://borokobo.web.fc2.com/index.html
Use Google Translate, head to the "Downloads" section, and look under the 
"Mega Man 4" heading to find the latest official release of the patch.
I will endeavor to keep this archive updated and host it on my site about 
Rockman 4MI: https://sites.google.com/site/rockman4mi/

Q: Who are you?
I'm just someone who enjoys this game and wants people to play it.

Q: What makes this game so great?
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.

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 and references to other games seamlessly into its levels.

The game has a fully customizable difficulty, so you can make it anything from
effortlessly easy to nearly impossible. And yet, the game has two preset
difficulties, and the game's Normal Mode hits the challenge sweet spot, for me;
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. If 
you want a challenge, the Hard Mode is quite tough, and it is possible to
configure the difficulty even higher than that.

Q: What are the configuration settings?
You can set the language to either Japanese or Engrish. An English version may
or may not come out at some point. The Engrish is bad, but intelligible.
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 critical hits and item drops, as they are random elements.
"Main" is the main difficulty setting. There are many differences between 
Normal and Hard Mode; too many to list all of them, but in general, it changes
the way enemies, bosses, and stages behave.
"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.
On the Normal Mode preset, 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 fills up all of your weapon energy by
10 points when you die. It makes the game a little easier. You can turn it off
if you don't like it.
The third is the Exchanger, which converts excess health into weapon energy.