NetReactorVMDecoder

It's not perfect. Use it only as a reference when decoding VM opcodes.
Tested only on 32bit exe with .NET Reactor v6.3.

How to use

VMDecoder <origin_assembly_path> [method_id]
//ex) VMDecoder C:\\path\\to\\YourApp.exe(dll) 0

When you decode awesome.exe, this is what you get.

using System;
using System.Text;

public class DecompiledValidator
{
    public string SomeFunction(SomeParameter)
    {
        string local0;
        object local1;
        object local2;
        object local3;
        object local4;
        object local5;
        object local6;
        object local7;
        object local8;
        object local9;
        object local10;
        object local11;
        int local12;

        var temp_0 = System.Convert.FromBase64String(serial);
        local1 = temp_0;
        var temp_1 = System.Linq.Enumerable.Take(32, local1);
        var temp_2 = System.Linq.Enumerable.ToArray(temp_1);
        local2 = temp_2;
        var temp_3 = System.Linq.Enumerable.Skip(32, local1);
        var temp_4 = System.Linq.Enumerable.Take(32, temp_3);
        var temp_5 = System.Linq.Enumerable.ToArray(temp_4);
        local3 = temp_5;
        var temp_6 = System.Linq.Enumerable.Skip(64, local1);
        var temp_7 = ((string)local1).Length;
        var temp_8 = Convert.ToInt32(temp_7);
        var temp_9 = (temp_8 - 64);
        var temp_10 = System.Linq.Enumerable.Take(temp_9, temp_6);
        var temp_11 = System.Linq.Enumerable.ToArray(temp_10);
        local4 = temp_11;
        var temp_12 = new System.Security.Cryptography.Rfc2898DeriveBytes(1000, local2, "[MethodImpl(MethodImplOptions.NoInlining)]", EMPTY_STACK);
        local5 = temp_12;
        var temp_13 = System.Security.Cryptography.DeriveBytes.GetBytes(32, local5);
        local6 = temp_13;
        var temp_14 = new System.Security.Cryptography.RijndaelManaged(EMPTY_STACK);
        local7 = temp_14;
        var temp_15 = System.Security.Cryptography.SymmetricAlgorithm.set_BlockSize(256, local7);
        var temp_16 = System.Security.Cryptography.SymmetricAlgorithm.set_Mode(1, local7);
        var temp_17 = System.Security.Cryptography.SymmetricAlgorithm.set_Padding(2, local7);
        var temp_18 = System.Security.Cryptography.SymmetricAlgorithm.CreateDecryptor(local3, local6, local7);
        local8 = temp_18;
        var temp_19 = new System.IO.MemoryStream(local4, EMPTY_STACK);
        local9 = temp_19;
        var temp_20 = new System.Security.Cryptography.CryptoStream(0, local8, local9, EMPTY_STACK);
        local10 = temp_20;
        var temp_21 = ((string)local4).Length;
        var temp_22 = Convert.ToInt32(temp_21);
        var temp_23 = new System.Byte[(int)temp_22];
        local11 = temp_23;
        var temp_24 = ((string)local11).Length;
        var temp_25 = Convert.ToInt32(temp_24);
        var temp_26 = System.IO.Stream.Read(temp_25, 0, local11, local10);
        local12 = temp_26;
        var temp_27 = System.IO.Stream.Close(local9);
        var temp_28 = System.IO.Stream.Close(local10);
        var temp_29 = System.Text.Encoding.get_UTF8();
        var temp_30 = System.Text.Encoding.GetString(local12, 0, local11, temp_29);
        local0 = temp_30;
    LABEL_88:
        if (!Convert.ToBoolean(local10)) goto INST_87;
        var temp_31 = System.IDisposable.Dispose(local10);
    INST_87:
        return null;
    LABEL_94:
        if (!Convert.ToBoolean(local9)) goto INST_93;
        var temp_32 = System.IDisposable.Dispose(local9);
    INST_93:
        return null;
    LABEL_100:
        if (!Convert.ToBoolean(local8)) goto INST_99;
        var temp_33 = System.IDisposable.Dispose(local8);
    INST_99:
        return null;
    LABEL_106:
        if (!Convert.ToBoolean(local7)) goto INST_105;
        var temp_34 = System.IDisposable.Dispose(local7);
    INST_105:
        return null;
    LABEL_112:
        if (!Convert.ToBoolean(local5)) goto INST_111;
        var temp_35 = System.IDisposable.Dispose(local5);
    INST_111:
        return null;
        return local0;

        return null; // Default return
    }
}