I just want to make a small remark about the filming sight. It is stated in the episode that that specific territory has been colonized by Portugal, and yet, the "natives" speak Spanish in the episode. Spanish and Portuguese are amongst the most spoken languages on the planet, so quite a few viewers can notice the mistake.
My vote for this episode would have been a well deserved 10, if it hadn't been for this detail. But details are also important, especially in such a production, so it's a 9.
Other than that - the show hasn't had a single boring episode so far! This one also falls in the same "category". A pleasure to watch, always, and season 5 is quite anticipated