The following are known Action Replay Codes for Marvel vs. Capcom 2 on SEGA Dreamcast (Dreamcast). These codes were also known as GameShark Codes and in most cases will work on both devices.

Device Compatibility: Action Replay & GameShark

P2 Combo Level 2
807FC128
00000002

P2 Combo Level 0
807FC128
00000000

Infinite Health P2
A6435E3B
00000090

P1 Combo Level 5
69532769
00000005

P1 Combo Level 4
69532769
00000004

P2 Combo Level 1
807FC128
00000001

P1 Combo Level 3
69532769
00000003

P2 Combo Level 3
807FC128
00000003

P2 Combo Level 4
807FC128
00000004

Infinite Health P1
D1C88C73
00000090

P1 Combo Level 0
69532769
00000000

No Health P1
D1C88C73
00000000

P2 Combo Level 5
807FC128
00000005

P1 Combo Level 1
69532769
00000001

Lots of Points
9CB004B5
0000270F

No Health P2
A6435E3B
00000090

P1 Combo Level 2
69532769
00000002