[kolkoo]

Well this is how I get the TLS Index and Value from W3.

DWORD GetIndex()
{
    return *(DWORD*)(0x6FAA45E4);
}
DWORD GetW3TlsForIndex(DWORD index)
{
    DWORD pid = GetCurrentProcessId();
    THREADENTRY32 te32;
    HANDLE hSnap=CreateToolhelp32Snapshot( TH32CS_SNAPTHREAD, pid );
    te32.dwSize = sizeof(THREADENTRY32);
    if ( Thread32First( hSnap, &te32 ) )
    {
        do 
        {
            if ( te32.th32OwnerProcessID == pid )
            {
                HANDLE hThread = OpenThread( THREAD_ALL_ACCESS, false, te32.th32ThreadID );
                CONTEXT ctx = { CONTEXT_SEGMENTS };
                LDT_ENTRY ldt;
                GetThreadContext( hThread, &ctx );
                GetThreadSelectorEntry( hThread, ctx.SegFs, &ldt );
                DWORD dwThreadBase = ldt.BaseLow|(ldt.HighWord.Bytes.BaseMid<<16)|(ldt.HighWord.Bytes.BaseHi<<24);
                CloseHandle( hThread );
                if ( dwThreadBase == NULL )
                    continue;
                DWORD *dwTLS = *(DWORD**)(dwThreadBase+0xE10+4*index);
                printf("Thread: %X , TLS for index %X : %X\n",te32.th32ThreadID,index,(DWORD)dwTLS);
                if ( dwTLS == NULL )
                    continue;
                return (DWORD)dwTLS;
                
            }
        } while( Thread32Next( hSnap, &te32 ) );
    }
    return NULL;
}

And this is how I get the current game state value after having already retrieved the TlsValue:

DWORD GetGameStateValue()
{
	DWORD rt;
	__asm
	{
		MOV ESI,0x0D;
		MOV EAX,TlsValue;
		MOV EAX, DWORD PTR DS:[EAX+ESI*4];
		MOV EAX,DWORD PTR DS:[EAX+0x10]
		MOV ECX,DWORD PTR DS:[EAX+0x8]
		MOV EAX, DWORD PTR DS:[ECX+0x278];
		MOV rt,EAX;
	}
	return rt;
}

And what made me think it wasn't used prior to patch 1.22 is that I didn't find any calls to TlsGetValue/TlsSetValue in 1.21b game.dll intermodular calls.