Here will only tell you a simplest way to skip multi-client detecting by official launcher (Mabinogi.exe), if you are seeking 'How to run multi-client against HackShield' please go [Only registered and activated users can see links. Click Here To Register...].
Just make one byte changed, currently tested on NA,TW,CN,EU.
I has used this for a long time, it should also work for future...
- Open Mabinogi.exe with any hex editor (UltraEdit.... etc).
- Find the pattern '85 C0 74 25 68 E8 03 00 00 FF', then modify to '85 C0 EB 25 68 E8 03 00 00 FF'
- Save it. :D (Don't forget to make a backup for original.)
Just make one byte changed, currently tested on NA,TW,CN,EU.
I has used this for a long time, it should also work for future...