Spoiler (click to reveal)
Once you go to the Isle of Dread, you draw and fight silvers. If defeated some of these allow you to leave the Island, some allow you to skip the next encounter, etc. Assif Shib Shah himself may potentially take control of your allies and have them attack you. So the end encounter can be pretty interesting, since there is a lot of variability on what you will face. You may face some strong silvers and not be ready for the end encounter. For me, I was ready for the end encounter with strong allies, but then Assif took my allies and used them against me, so I died. In this game there is a heavy emphasis on getting map tokens to get you legendary items, that will help you win the end encounter.