Fowl Play is a missable achievement in Immortals of Aveum. You can only unlock it during Chapter 12 of the main story campaign. When playing the “Colossal” mission, you are treated with a cinematic of Jak, Deyvn, and Zendara drinking all night long. A bird appears on the table during this cutscene. Only from that moment, you are able to obtain the Fowl Play Achievement.
The bird is located in the Palathon. You can find it behind The Forge in the Hall of Memories. Use the portal to get to the lower floor of the Palathon. You have the Fast Travel Portal on one side of the Grand Hall and a local portal through the doors on the other side of the Grand Hall.
Once you are in the Hall of Memories, you need to walk down the stairs. There is one more staircase towards the zone exit that leads to The Forge. You will find the bird sitting behind this station. The achievement will unlock by simply walking up to the bird.