In short, here's how:
1) Open [game folder]\data\data.pak with WinRAR.
2) Find the file you need to modify. To strengthen bone dragons, it will be \GameMechanics\Creature\Creatures\Necropolis\Bone_Dragon.xdb; open it with Notepad.
3) Make the changes. It's all quite obvious; you just need to know a little English.
4) Save the modified file, but not in our archive, but in a new one, with the extension zip. The archive name is arbitrary; the structure (i.e., the path to the saved file inside the archive) must match the structure of data.pak.
5) Change the extension from zip to h5u. The mod is ready!
И пока в кармане пачка милкиуэйев - значит все не так уж плохо на сегодняшний день