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

Yes, I played Heroes 4! So I understand. Are we talking about showing the hero's path to a specific cell not as in Heroes 3 - safe, but sometimes too long (going around), but as the shortest path, which may pass by/through neutral creatures, and you might have to fight them? And this path is then shown in yellow? Well, then it can sometimes be useful, but I'm already used to the "Heroes 3" version.