Updated:
Setting "debug_command_mode = active" in ptemplate.conf has the same effect as Method 1 below, for those who do not want to patch their gs.
Method 1
This is another way to patch to allow GMs to create monsters/creatures from the GM console. This method will(hopefully) work for all future versions starting from v70.
1. Load gs in a hex editor that allows you to search for specific byte sequences.
2. Search for the following bytes:
3. Replace them with:0F B6 80 A4 18 00 00 C9 C3
4. Save your work and upload gs to your server.90 90 33 C0 83 C0 01 C9 C3
Note: This fix will enable "Debug Mode" on the server side for every player. As far as I'm concerned this only affects these two GM console features, something related to terrain, and a function called SetCooldown.
Method 2
For those who do not want the extra burden of an unstable fix, the following is another method just to fix create monster/creature.
1. Load gs in a hex editor.
2. Go to the following offsets depending on the version of gs you have:
3. Change the bytes 75 05 at each offset to EB 05.v70 0x000C92AE 0x000C9046 v80 0x000CD6DF 0x000CD947
4. Save your work and upload gs back to your server
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