Maybe you were playing with just one player? I understand if there aren't many fighters available, but why is the invisibility lasting for 3 turns? You probably had a hero around level 30, I wouldn't be surprised. But I'll definitely check this out in the second week. In my opinion, it's utter nonsense.
Added 3 minutes later
P.S. And to make it easier for you, on the "Lands of Outcasts" map (which you know well), there are several magic fountains, so taking Utopia in the second week is more than possible. :)
