Why does the shadow curse discourage exploration?
I say that mostly because there's a steep jump in difficulty, tough new enemies with devastating new abilities, unpredictable environmental conditions, a sense of looming dread and stark scary contrast to Act I. I was definitely on edge and have seen the sentiment echoed a few times. And it turns out that wariness is warranted. Not for the shadow curse, but for the poorly designed Isobel event.
And the WORST part is this fight is so FUCKING critical to EVERYTHING.
The messed up thing is I didn't fully realize what had happened until I was far beyond it. The only reason was the tension with Karlach was just too much to bear so I went googling (something I was trying to avoid to prevent spoilers and really enjoy the world.)
Imagine this D&D campaign:
About 6 sessions in, your DM presents a random encounter.
Your party has terrible dice rolls and ends up with low initiative.
As a result they don't get to act before a random new NPC who was introduced 3 minutes ago gets ganked.
It's a super difficult fight and your party barely made it out alive.
Now it's session 12. Work has been brutal, inflation's out of control, your friend group is struggling to find time to get together, but they've committed for 12 weeks and your campaign is miraculously still going strong. You've had dozens of encounters. Lots of close calls and great loot found. Your characters have bonded and grown immensely. Your party is finally feeling like they're gaining the upper hand after a lot of brutal sessions.
As you're all on your way out the door, your DM says:
"Oh hey, remember that encounter at that inn 6 sessions ago? I didn't mention it at the time, but there was a character crucial to your campaign in a stable near that inn. You had no reason to suspect he would be there because he specifically told you to look for him somewhere else entirely. Anyway, he's dead. And I've decided that you can't resurrect him. And you can't cast Speak With Dead on him. And no one else can help you on the quest. Anyway, you failed 6 sessions ago. I guess I probably should have mentioned it. Everything you've just done for the past 6 sessions has been for naught. Have a good night everyone! And no, you didn't level up."