HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

Is breath really better than a blade? I think the opposite.

Maybe you can explain why? Because no one here understands your position.

Breath on top of the blade is everything that's in the blade, plus everything that's in the breath, plus some bugs have been fixed.
From this, it clearly follows that breath on top of the blade is at least not worse than the blade, and in my opinion, it is obviously better.
If you're not aware, breath on top of the blade and breath separately are different things. Breath on top of the blade is almost the same as the complete collection.

I found time to check: to turn the blade into <breath on top of the blade>, you just need to put the Sod's h3bitmap.lod, h3sprite.lod, heroes3.snd, and video.vid (total 234 MB) into the 'data' folder and install HD. Launching h3blade.exe will give you a regular blade, launching Heroes3HD.exe will give you breath on top of the blade in HD.