Which file needs to be edited to change a hero’s specialization?

...Several problems have arisen:
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If anyone knows, please let me know which resource file I need to look into, or maybe it's in the .exe file, and provide detailed instructions. Thank you all in advance)).

You should contact the Wog forums, either this one http://forum.df2.ru/index.php?showforum=4 or this one www.wforum.heroes35.net, or even this one on PD /forum/section/17/. Basically, everything you described can be done quickly; you just need to take WoG, remove all the scripts that don't interest you, and write your own scripts. The rest of the gameplay won't change. There is no need to dig around in the executable file unless it's a very radical case; all changes are made by editing text files from h3bitmap.lod, and after that, these files only need to be placed in the data folder for them to work. By the way, regarding platinum, it seems buggy in this regard because it was subjected to modifications by Bukovets; it's better to use the SoD 3.2 executable or directly the WoG executable.

Regarding templates, perhaps you are not packing rmg.txt back into .lod correctly. It's better to place it directly in the data folder and edit the file itself, removing all unnecessary templates. This can be conveniently done using Excel. To generate only the template you want, it must be the only one in the file, or it alone must meet the generation conditions, which include map size (including underground), the number of human players, and the number of computer players. Water and monsters do not affect generation