Lake of Wisdom

The Lake of Wisdom is a lake in front of the Mighty Eagle's cave. Mighty Eagle commonly urinates in it.

The Angry Birds Movie
After discovering the Mighty Eagle's cave, Red, Chuck, and Bomb the legendary lake. Chuck and Bomb then gargled, swam, and drank the water of the lake. After hearing the footsteps of Mighty Eagle, they looked up in awe at the legendary hero, before discovering he actually urinates in the lake, much to their disgust.