It was a powerful scene. What I wonder about is why Amon had his "scar"("?") when/after he was in the water, but not when he walked into Tarlokk's cell. The water didn't wash it off, so perhaps it is real. Additionally, Amon did not know when/if he would take off his mask, so why would he have the "scar" on at the rally?Remember that plastic surgery exists, so it is possible that the man in the boat was a decoy.