Heroes 6 - Discussion

Is this spell worth investing in if such situations only occur two or three times throughout the entire game?

I always take my time with the game. What's the point of playing if you don't have time to experience all the game has to offer? To cast cool spells, acquire powerful artifacts, and orchestrate massive battles... Unless you just want to compete to see who can win faster. But that's not for me. For the same reason, I hated the AI in Heroes 5. It simply didn't let you savor the map – it was constantly aggressive, even if it knew it would lose.