[Unpacking] MapleStory (Themida)

I have been reverse engineering for a long time. However, I have never attempted to unpack Themida. I know how to manually unpack easier protectors using ImpRec & OllyDump. My question is, how can I get better so that I can unpack Themida?

I want to unpack Themida for the following reason:

While reverse engineering GameLauncher.exe I found that:

GameLauncher:

Code:

        PUSH -1
        PUSH GameLaun_00401FB9               ; Entry address
        MOV EAX,DWORD PTR FS:[0]
        PUSH EAX
        MOV DWORD PTR FS:[0],ESP
        SUB ESP,0140h
        PUSH ESI
        MOV ESI,ECX
        LEA EAX,DWORD PTR SS:[ESP+034h]
        LEA ECX,DWORD PTR SS:[ESP+018h]
        PUSH EAX
        PUSH ECX
        PUSH 0
        PUSH 0Fh
        PUSH 0
        PUSH 0
        PUSH 0
        PUSH GameLaun_00403160               ; ASCII "SOFTWARE\\Wizet\\MapleStory"
        PUSH 080000002h
        MOV DWORD PTR SS:[ESP+028h],0
        CALL DWORD PTR DS:[<&ADVAPI32.RegCreateKeyExA>] ; ADVAPI32.RegCreateKeyExA
        LEA ECX,DWORD PTR SS:[ESP+024h]
        CALL #540                            ;<= Jump/Call Address Not Resolved
        LEA EDX,DWORD PTR SS:[ESP+02Ch]
        LEA EAX,DWORD PTR SS:[ESP+03Ch]
        PUSH EDX
        MOV EDX,DWORD PTR SS:[ESP+01Ch]
        LEA ECX,DWORD PTR SS:[ESP+03Ch]
        PUSH EAX
        PUSH ECX
        PUSH 0
        PUSH GameLaun_00403154               ; ASCII "ExecPath"
        PUSH EDX
        MOV DWORD PTR SS:[ESP+0164h],0
        MOV DWORD PTR SS:[ESP+044h],0104h
        CALL DWORD PTR DS:[<&ADVAPI32.RegQueryValueExA>] ; ADVAPI32.RegQueryValueExA
        TEST EAX,EAX
        JE @GameLaun_0040165D
        MOV ECX,ESI
        CALL @GameLaun_00401880              ;<= Jump/Call Address Not Resolved
        TEST EAX,EAX
        JNZ @GameLaun_00401844
        PUSH EAX
        PUSH EAX
        PUSH GameLaun_00403108               ; ASCII "Cannot locate the game installation path. Please check the installation."
        MOV ECX,ESI
        CALL #4224                           ;<= Jump/Call Address Not Resolved
        JMP @GameLaun_00401844

@GameLaun_0040165D:

        LEA EAX,DWORD PTR SS:[ESP+03Ch]
        PUSH EBX
        PUSH EAX
        LEA ECX,DWORD PTR SS:[ESP+010h]
        CALL #537                            ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+02Ch]
        PUSH 1
        PUSH ECX
        LEA ECX,DWORD PTR SS:[ESP+014h]
        MOV BYTE PTR SS:[ESP+0158h],1
        CALL #5710                           ;<= Jump/Call Address Not Resolved
        MOV EAX,DWORD PTR DS:[EAX]
        PUSH GameLaun_00403104
        PUSH EAX
        MOV BYTE PTR SS:[ESP+0158h],2
        CALL DWORD PTR DS:[<&MSVCRT._mbscmp>] ; msvcrt._mbscmp
        ADD ESP,8
        TEST EAX,EAX
        JNZ @GameLaun_004016C8
        LEA EDX,DWORD PTR SS:[ESP+0Ch]
        PUSH GameLaun_004030F4               ; ASCII "MapleStory.exe"
        LEA EAX,DWORD PTR SS:[ESP+018h]
        PUSH EDX
        PUSH EAX
        CALL #924                            ;<= Jump/Call Address Not Resolved
        MOV EBX,1
        MOV DWORD PTR SS:[ESP+8],EBX
        MOV BYTE PTR SS:[ESP+0150h],3
        JMP @GameLaun_00401713

@GameLaun_004016C8:

        LEA ECX,DWORD PTR SS:[ESP+0Ch]
        PUSH GameLaun_00403104
        LEA EDX,DWORD PTR SS:[ESP+028h]
        PUSH ECX
        PUSH EDX
        CALL #924                            ;<= Jump/Call Address Not Resolved
        MOV DWORD PTR SS:[ESP+8],2
        PUSH GameLaun_004030F4               ; ASCII "MapleStory.exe"
        PUSH EAX
        LEA EAX,DWORD PTR SS:[ESP+03Ch]
        MOV DWORD PTR SS:[ESP+0158h],4
        PUSH EAX
        CALL #924                            ;<= Jump/Call Address Not Resolved
        MOV EBX,6
        MOV DWORD PTR SS:[ESP+8],EBX
        MOV DWORD PTR SS:[ESP+0150h],5

@GameLaun_00401713:

        PUSH EAX
        LEA ECX,DWORD PTR SS:[ESP+014h]
        CALL #535                            ;<= Jump/Call Address Not Resolved
        TEST BL,4
        MOV DWORD PTR SS:[ESP+0150h],0Ah
        JE @GameLaun_0040173D
        AND EBX,FFFFFFFB
        LEA ECX,DWORD PTR SS:[ESP+034h]
        MOV DWORD PTR SS:[ESP+8],EBX
        CALL #800                            ;<= Jump/Call Address Not Resolved

@GameLaun_0040173D:

        TEST BL,2
        MOV DWORD PTR SS:[ESP+0150h],9
        JE @GameLaun_0040175D
        AND EBX,FFFFFFFD
        LEA ECX,DWORD PTR SS:[ESP+024h]
        MOV DWORD PTR SS:[ESP+8],EBX
        CALL #800                            ;<= Jump/Call Address Not Resolved

@GameLaun_0040175D:

        TEST BL,1
        MOV DWORD PTR SS:[ESP+0150h],8
        JE @GameLaun_0040177D
        AND EBX,FFFFFFFE
        LEA ECX,DWORD PTR SS:[ESP+014h]
        MOV DWORD PTR SS:[ESP+8],EBX
        CALL #800                            ;<= Jump/Call Address Not Resolved

@GameLaun_0040177D:

        LEA ECX,DWORD PTR SS:[ESP+02Ch]
        MOV DWORD PTR SS:[ESP+0150h],7
        CALL #800                            ;<= Jump/Call Address Not Resolved
        PUSH GameLaun_004030E4               ; ASCII " GameLaunching"
        LEA ECX,DWORD PTR SS:[ESP+024h]
        CALL #537                            ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+010h]
        PUSH EAX
        LEA EDX,DWORD PTR SS:[ESP+01Ch]
        MOV 0BhL,0B
        PUSH ECX
        PUSH EDX
        MOV BYTE PTR SS:[ESP+015Ch],BL
        CALL #922                            ;<= Jump/Call Address Not Resolved
        PUSH EAX
        LEA ECX,DWORD PTR SS:[ESP+014h]
        MOV BYTE PTR SS:[ESP+0154h],0Ch
        CALL #858                            ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+018h]
        MOV BYTE PTR SS:[ESP+0150h],BL
        CALL #800                            ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+020h]
        MOV BYTE PTR SS:[ESP+0150h],7
        CALL #800                            ;<= Jump/Call Address Not Resolved
        MOV EAX,DWORD PTR SS:[ESP+0Ch]
        PUSH EAX
        CALL DWORD PTR DS:[<&KERNEL32.SetCurrentDirectoryA>] ; kernel32.SetCurrentDirectoryA
        MOV ECX,DWORD PTR SS:[ESP+010h]
        PUSH 5
        PUSH ECX
        CALL DWORD PTR DS:[<&KERNEL32.WinExec>] ; AcLayers.71C21A97
        CMP EAX,01Fh
        POP EBX
        JA @GameLaun_00401822
        MOV ECX,ESI
        CALL @GameLaun_00401880              ;<= Jump/Call Address Not Resolved
        TEST EAX,EAX
        JNZ @GameLaun_00401822
        PUSH EAX
        PUSH EAX
        PUSH GameLaun_004030A8               ; ASCII "Failed to execute the game. Please check the installation."
        MOV ECX,ESI
        CALL #4224                           ;<= Jump/Call Address Not Resolved

@GameLaun_00401822:

        LEA ECX,DWORD PTR SS:[ESP+0Ch]
        MOV BYTE PTR SS:[ESP+014Ch],1
        CALL #800                            ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+8]
        MOV BYTE PTR SS:[ESP+014Ch],0
        CALL #800                            ;<= Jump/Call Address Not Resolved

@GameLaun_00401844:

        MOV ECX,ESI
        CALL #4853                           ;<= Jump/Call Address Not Resolved
        LEA ECX,DWORD PTR SS:[ESP+024h]
        MOV DWORD PTR SS:[ESP+014Ch],-1
        CALL #800                            ;<= Jump/Call Address Not Resolved
        MOV ECX,DWORD PTR SS:[ESP+0144h]
        POP ESI
        MOV DWORD PTR FS:[0],ECX
        ADD ESP,014Ch
        RETN

MapleStory will only execute if the command parameter is 'GameLaunching'

My goal is to reverse engineer MapleStory so that I can find out where it is checking to see if the 'GameLaunching' parameter is there, so that I can patch that and the function. I also want to make hacks and contribute to the forum. The only problem is Themida.

Does anybody have any advice for me? Any tutorials that will make my skill in reverse engineering get more advanced? Or possibly any up to date tutorials on unpacking themida?

Thank you.

[Unpacking] MapleStory (Themida)

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