Mega Man II

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Mega Man II is the sequel to Mega Man. The game is still a platform run-and-gun where you play Rock. Dr. Wily has created eight new robots to thwart Dr. Light. Rock must enter each robot's stage, fight his way to them, and vanquish them to steal their powers.

Easy Cheats

Icon Addr Val Cmp Description
Icon-Lives.png 8073 09 03 Start With 9 Lives
Icon-Lives.png 8073 63 03 Start With 99 Lives
Icon-Lives-Infinite.png 00A8 0B - Infinite Lives
Icon-HitPoints-Infinite.png 06C0 1C - Infinite Hit Points
Icon-Powerup.png 00A7 04 - Infinite Energy Tanks
Icon-Invincible.png 004B 01 - Invulnerable
Icon-Ammo-Infinite.png 009C 1C - Infinite Atomic Fire
Icon-Ammo-Infinite.png 009D 1C - Infinite Air Shooter
Icon-Ammo-Infinite.png 009E 1C - Infinite Leaf Shield
Icon-Ammo-Infinite.png 009F 1C - Infinite Bubble Lead
Icon-Ammo-Infinite.png 00A0 1C - Infinite Quick-Boomerang
Icon-Ammo-Infinite.png 00A1 1C - Infinite Time-Stopper
Icon-Ammo-Infinite.png 00A2 1C - Infinite Metal-Blade
Icon-Ammo-Infinite.png 00A3 1C - Infinite Crash Bomber
Icon-Item.png 009B FF - Have All Items
Icon-Ammo-Infinite.png 00A4 1C - Infinite Item-1
Icon-Ammo-Infinite.png 00A5 1C - Infinite Item-2
Icon-Ammo-Infinite.png 00A6 1C - Infinite Item-3
Icon-Warp.png 009A FF - All Bosses Defeated
Icon-Jump.png 003C 07 - High Jump
Icon-Jump.png 003C 10 - Super High Jump
Icon-Jump.png 0030 10 - Moon Gravity (Affects some enemies)
Icon-Strength.png 8118 0E 1C Bosses Have Half Hit Points
Icon-Strength.png 8118 01 1C Bosses Have 1 Hit Point
Icon-Speed.png DA09 02 04 Quickman's Beams Half Speed
Icon-Challenge.png 8073 01 03 Start With 1 Life
Icon-Challenge.png 8118 38 1C Bosses Have Double Hit Points
Icon-Challenge.png D78E 28 14 Most Enemies Have Double Hit Points
Icon-Challenge.png DA09 05 04 Quickman's Beams Even Faster
How do I use these?

North America

Mega Man II.png

Memory Addresses

001C - Program Counter

0023 - Controller 1 Poll
0022 - Controller 2 Poll
0025 - Controller 1 Poll Mirror
0026 - Controller 2 Poll Mirror

003C - Jump Height (04 - Normal, 05 - In Water)

004B - Invulnerable Timeout

009A - Weapons Bit Flag (Turning all on will take you right to Dr. Wily Stage 1 after the next victory)
	+01 - Atomic Fire
	+02 - Air Shooter
	+04 - Leaf Shield
	+10 - Quick-Boomerang
	+20 - Time-Stopper
	+40 - Metal-Blade
	+80 - Crash Bomber
009B - Item Bit Flag
	+01 - Item-1
	+02 - Item-2
	+04 - Item-3
009C - Atomic Fire (Heat Man) (00-1C)
009D - Air Shooter (Air Man) (00-1C)
009E - Leaf Shield (Wood Man) (00-1C)
009F - Bubble Lead (Bubble Man) (00-1C)
00A0 - Quick-Boomerang (Quick Man) (00-1C)
00A1 - Time-Stopper (Flash Man) (00-1C)
00A2 - Metal-Blade (Metal Man) (00-1C)
00A3 - Crash Bomber (Crash Man) (00-1C)
00A4 - Item-1 (00-1C)
00A5 - Item-2 (00-1C)
00A6 - Item-3 (00-1C)
00A7 - Energy Tanks (00-04)
00A8 - Lives (00-64)
00A9 - Active Suit

00B6 - moves background vertically
00B8 - moves background horizontally
00E0-00E3 - SFX on/off (music left)
00E4 - sound on/off
00E7 - music tempo (00-0D), can cause slowdown/crash

017D-017F - Object Y

0356-0375 - PPU Palette

043D-043F - Object Type ?

0440 - Player X on Map x256
0460 - Player X on Map x1

0473-047F - Quickman Beams Location

04A0 - Player Y on Map x1

0613-061E - Quickman Beams Speed

0640 - Player Y Delta

06D0-06DF - Enemy Hit Points

06F0-06FF - Enemy Hit Type?

06C0 - Hit Points (00-1C)
06C1 - Boss Hit Points (00-1C)

8118 - Bosses Max Hit Points (1C)

9233 - Dr. Wily Stage 2 Boss Max Hit Points (1C)

D78E - Generic Enemy Hit Points (14) - Most enemies in a level use this for hit points, however, each has a different armor level.

DA09 - Quickman Beam Speed (04)

E08C - Crash Bomb Time Delay (7F)


Code

Starting Lives

8072:A9 03     LDA #$03       ; Load 3 into A.
8074:85 A8     STA $00A8      ; Store A into Player Lives.

Increment Boss Hit Points

This subroutine increments the Boss's hit points one point. It also plays the HP increment sound effect once every 3 times through this routine.

812F:A5 1C     LDA $001C      ; Load Program Counter.
8131:29 03     AND #$03       ; AND Program Counter with 03.
8133:D0 08     BNE $813D      ; If not a multiple of 3, skip the sound effect.
8135:EE C1 06  INC $06C1      ; Increment Boss HP
8138:A9 28     LDA #$28       ; Load HP Gain sound effect.
813A:20 51 C0  JSR $C051      ; Play Sound effect.
813D:60        RTS

Increment Dr. Wily Stage 2 Boss Hit Points

A118:A5 1C     LDA $001C      ; Load Program Counter.
A11A:29 03     AND #$03       ; AND Program Counter with 03.
A11C:D0 0F     BNE $A12D      ; If not a multiple of 3, skip the sound effect.
A11E:AD C1 06  LDA $06C1      ; Increment Boss HP
A121:C9 1C     CMP #$1C       ; Compare A with $1C
A123:F0 08     BEQ $A12D      ; If Boss Hit Points = $1C, leave (HP is compare again outside of this subroutine).
A125:EE C1 06  INC $06C1      ; Increment Boss Hit Points.
A128:A9 28     LDA #$28       ; Load HP Gain sound effect.
A12A:20 51 C0  JSR $C051      ; Play Sound effect.
A12D:60        RTS

Sound Effects Table

00 - Flashman Stage
01 - Woodman Stage
02 - Crashman Stage
03 - Heatman Stage
04 - Airman Stage
05 - Metalman Stage
06 - Quickman Stage
07 - Bubbleman Stage
08 - Dr. Wily Stage 1
09 - Dr. Wily Stage 2
0A - Game Start
0B - Boss
0C - Stage Select
0D - Title
0E - Opening
0F - Game Over
10 - Password
11 - Dr. Wily Map
12 - Dr. Wily Ship Sound FX
13 - Ending
14 - Staff Roll
15 - Stage Clear
16 - All Stage Clear
17 - Get a Weapon
18 - Game Over
19 - Game Over
1A - Game Over
1B - Game Over
1C - Game Over
1D - Game Over
1E - Game Over
1F - Game Over
20 - Game Over
21 - Spiked Chain Platform
22 - Explosion
23 - Metal Blade
24 - Bubble Lead?
25 - ?
26 - Crash Bomb?
27 - Quickman Beam
28 - Hit Point Increment
29 - ?

Text

The text in Mega Man II is even harder to deal with than the original. There are a couple of character sets in the ROM including a full Japanese set left in. The sets are loaded into various locations in memory when they're used, so the tables are even more useful than normal when hacking the game text.

Title

00= 
A0=0
A1=8
A2=2
A3=©
A4=t
A5=9
A6=m
A7=1
C0= 
C1=A
C2=B
C3=C
C4=D
C5=E
C6=F
C7=G
C8=H
C9=I
CA=J
CB=K
CC=L
CD=M
CE=N
CF=O
D0=P
D1=Q
D2=R
D3=S
D4=T
D5=U
D6=V
D7=W
D8=X
D9=Y
DA=Z
DB=®
DC=.
DD=,
DE='
DF=!

Menu

95=N
96=E
97=X
98=T
99=W
9A=F
9B=A
9C=Q
9D=B
9E=M
9F=H
A0=C
A1=»
A2=>
A3=@
A4=0
A5=1
A6=2
A7=3
A8=4
A9=5
AA=6
AB=7
AC=8
AD=9
AE=:
AF=P

Stage Select / Credits

01=A
02=B
03=C
04=D
05=E
06=F
07=G
08=H
09=I
0A=J
0B=K
0C=L
0D=M
0E=N
0F=O
10=P
11=Q
12=R
13=S
14=T
15=U
16=V
17=W
18=X
19=Y
1A=Z
1B=®
1C=.
1D=,
1E='
1F=!
20= 

Password / Cut Scenes

40= 
41=A
42=B
43=C
44=D
45=E
46=F
47=G
48=H
49=I
4A=J
4B=K
4C=L
4D=M
4E=N
4F=O
50=P
51=Q
52=R
53=S
54=T
55=U
56=V
57=W
58=X
59=Y
5A=Z
5B=®
5C=.
5D=,
5E='
5F=!
94=-
A0=0
A1=1
A2=2
A3=3
A4=4
A5=5
A6=6
A7=7
A8=8
A9=9


Japan

Rockman 2 - Dr Wily no Nazo.png

The original name of Mega Man II is ロックマン2 Dr.ワイリーの謎 (Rockman 2: Dr. Wily no Nazo) Translated to "Rockman 2: The Mystery of Dr. Wily".


Europe

Mega Man II (E).png