Mega Man 4 Action Replay Codes (USA)
This page contains the Action Replay codes that I have available for Mega Man 4 (USA), a game for the original NES (Nintendo Entertainment System). If you're playing on an emulator, you'll typically be able to put these codes into the program through a built in option. Anyone who is really old school and playing on a physical console will have to purchase a physical Action Replay device to use these codes.
When it comes to emulation for the NES you have 3 good options to choose from. You can do RetroArch, Nestopia or MesenCE, follow the links provided to learn more about how to use the codes you find on this page on the Emulator of your choice. If you don't see the code you want on this page, I recommend you return to my Mega Man 4 Guides Index and choose a different section.
Infinite Lives: 00A1:09
Infinite Health: 00B0:9F
Untouchable: 003C:1F
Big Jump: 03D8:81
Use at your own risk, has drawbacks
Climb Anywhere: 0045:20
Enable it during the level. Turn off to use boss doors
Infinite Slide: 0034:10
Super Jump: 0041:60
You can't dismount ladders while this is on. Unless you use with the Climb Anywhere code.
Straight to Wily's Area: 00A9:FF
Title screen music modifier: 887A:??:12
Checkpoint Modifier: 001F:??
Infinite Time For Rush Coil: 0484:FE
No Enemies: C773:FF
Disable this code before facing bosses. It may also remove some needed platforms throughout levels
Robot Masters Have No Invulnerability Time: 05CF:00
Checkpoint Modifier - Always start at the beginning of the stage: 001F:00
Checkpoint Modifier - Always start at the halfway point of the stage: 001F:01
Checkpoint Modifier - Always start at just before the stage's boss: 001F:02
No Boss Health
Only turn this code on when the bosses health is fully loaded in
00BF:00
0467:00
Start At Second Group of Dr. Cossack Stages
00A9:FF
00AA:63