Decode / Encode MythicRC4Packet

        public static byte[] DecodeMythicRC4Packet(byte[] buf, byte[] sbox)
        {
            if (buf == null) return null;
            if (sbox == null) return null;
            byte[] tmpsbox = new byte[256];
            Array.Copy(sbox, 0, tmpsbox, 0, sbox.Length);
            byte i = 0;
            byte j = 0;
            ushort len = (ushort)((buf[0] << 8) | buf[1] + 10); //+10 byte for packet#,session,param,code,checksum
            int k;
            for (k = (len / 2) + 2; k < len + 2; k++)
            {
                i++;
                byte tmp = tmpsbox[i];
                j += tmp;
                tmpsbox[i] = tmpsbox[j];
                tmpsbox[j] = tmp;
                byte xorKey = tmpsbox[(byte)(tmpsbox[i] + tmpsbox[j])];
                buf[k] ^= xorKey;
                j += buf[k];
            }
            for (k = 2; k < (len / 2) + 2; k++)
            {
                i++;
                byte tmp = tmpsbox[i];
                j += tmp;
                tmpsbox[i] = tmpsbox[j];
                tmpsbox[j] = tmp;
                byte xorKey = tmpsbox[(byte)(tmpsbox[i] + tmpsbox[j])];
                buf[k] ^= xorKey;
                j += buf[k];
            }
            return buf;
        }

        //From DOL
        public static byte[] EncodeMythicRC4Packet(byte[] buf, byte[] sbox, bool udpPacket)
        {
            if (buf == null) return null;
            if (sbox == null) return null;
            byte[] tmpsbox = new byte[256];
            Array.Copy(sbox, 0, tmpsbox, 0, sbox.Length);
            byte i = 0;
            byte j = 0;
            ushort len = (ushort)((buf[0] << 8) | buf[1]);
            len += 1; // +1 byte for packet code
            if (udpPacket)
                len += 2; //+2 byte for packet-count

            int k;
            for (k = (len / 2) + 2; k < len + 2; k++)
            {
                i++;
                byte tmp = tmpsbox[i];
                j += tmp;
                tmpsbox[i] = tmpsbox[j];
                tmpsbox[j] = tmp;
                byte xorKey = tmpsbox[(byte)(tmpsbox[i] + tmpsbox[j])];
                j += buf[k];
                buf[k] ^= xorKey;
            }
            for (k = 2; k < (len / 2) + 2; k++)
            {
                i++;
                byte tmp = tmpsbox[i];
                j += tmp;
                tmpsbox[i] = tmpsbox[j];
                tmpsbox[j] = tmp;
                byte xorKey = tmpsbox[(byte)(tmpsbox[i] + tmpsbox[j])];
                j += buf[k];
                buf[k] ^= xorKey;
            }
            return buf;
        }