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@o      .;o ;;.;o    oo   ,O; ;ooo ,@@o;.  .;oOO@##@@@@@@@##@Oo                
@o  ;.,;.o. ,,.,o ;; ;O,  ;O; ;ooo.,ooOo;oO##@OOOOOOOOOOOOOOOO##o.             
@o,;o;o;;;;,oo,;;,;O,;o;;,OO;;,;oo;,,,Oo@@@OOOOOOOOOOOOOOOOOOOO@#O             
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                .o#@;@###################@@OOOOO@#Oo,.                         
                  ;####################@OOOOO@#@o,                             
                  ..O###############@OOOOO@#Oo,                                
                     ,o@#########@OOOOO@#@o;        ;oOoo;                     
                      . .;@###@OOOO@@#@o.      .,;OO#@@###o.                   
                      ;o@#@@OOOO@@###@@OOOOO@@@@##@OOO##O,                     
                   .o@#@@OOOOOOOOOOOOOOOOOOOOOOOOOOO##O,                       
                 ,o##@OOOOOOOOOOOOOOOOOOOOOOOOOOOO##O,                         
                o##@OOOOOOOOOOOOOOOOOOOOOOOOOOOO##O;                           
              ;O#########@##@##@###@##@##@##@###O; 

The founder of GameFAQs, Jeff "CJayC" Veasey, once wrote an excellent FAQ for the Dreamcast version of MVC2:

www.gamefaqs.com/console/dreamcast/file/...

The detailed description of the VMS file (save game) memory map reveals some interesting info about how to unlock all 56 characters, hidden stages, etc.  One thing that very few players actually were able to achieve on their own without cheating is the ability to select the same character multiple times - this required a save file at Level 99 with all other options unlocked.

=-------------------=
=VMS File Memory Map=
=-------------------=
(NOTE: This map is in DCI format, not the original VMS format.)

0000-009F: Standard VMU Header
           0064: Standard VMU Checksum
00A0-029F: Save Icon
02A0-02AB: UNKNOWN
02AC-02AD: D Points
02AE     : % of Current Level
02AF     : Current Level (Maxes at 99 naturally)
02B0-02B1: V Points
02B2-02B3: N Points
02B4-02BB: Available Characters (Bit setting, all = F8FF FFFF 07FF FFFF)
02BC-02C3: Available Costumes (Bit setting, all = F8FF FFFF 07FF FFFF)
02C4-02C6: Time Played
02C7     : Hidden Stages Available (Maxes at 7 naturally)
02C8-02D3: UNKNOWN
02D4-04B3: Arcade Mode High Scores (24 Bytes X 20)
04B4-0553: UNKNOWN
0554-0733: Score Attack Mode High Scores (24 Bytes X 20)
0734-0735: Number of times Versus Mode played
0736-0737: Number of characters picked in Arcade Mode
0738-0739: Number of times Training Mode played
073A-073B: Number of times Score Attack Mode played
073C-098F: Number of times character selected
           08A0-0917: Number of times selected in Training Mode
0990-09C3: Game Options
09C4-09C5: Checksum-16 of 02A0-09C3
09C6-09C7: Additive Checksum of 02A0-09C3
09C8-09FF: UNKNOWN, Most Likely Blank Padding