Patience is important with optical illusions like this one. Rather than quickly scanning the picture, move your eyes slowly across each section. Look for shapes that seem unusual or out of place, and consider whether shadows, mountain peaks, or parts of the eagle could form recognizable human features.
The illusion works because the artist has blended the hidden figure into natural elements. Your brain initially focuses on the most recognizable objects—the eagle and mountains—and tends to ignore shapes that do not immediately appear meaningful.
