Hi, it's me again.

Both players have the same unique character in the discard pile and the Secret of the North Woods triggers. What happens? What if either of the players has two copies in the discard pile at the time (creating a 2:1 situation)?

Hi!

First question : your unique caracter comes into play, The opponent does the same thing. You can play only one copy of an unique card, but it doesn't matter if you opponent plays the same card.

2.1 : You can put into play only one copy of an unique card. So, you will put into play only one copy of your unique card.