XeNTaX

Battle Mages uses 2 formats;

-GSM
-SAM

(Units also have an .mrk file, it's just a renamed .tga)

They seem to be same thing, except the latter is skinned.
The animations seems to be packed in SAM too.


Sample (GSM/SAM)

I have made a tool to edit these:
https://ermaccer.github.io/posts/miracle3d-designer/

humantent1.gsm 0x20 - vertex block length (divide by vertex stride to get number of vertices)
0x24 - vertex block start address
0x30 - face indices length (divide by 2 to get number of faces)
0x34 - face indices start address

edit
and here is h2o file for first submesh of berzerker.sam