Soluzar40,627 Locked 17 Oct 2021 17 Oct 2021
During the story quest "The Lizard's Mask" a priest will drug Bayek, causing him to enter a dream sequence. In the dream sequence you will have to defeat a giant snake, using a bow. It isn't very difficult, but does take quite a bit of time.
Once the dream sequence is over, you'll get the achievement.