Theme 8-3 AKA "Ethan's Theme" is the 33rd level in Danger Above. There is an Easter egg in the level that you can see when you shoot a bird upwards or zoom out(it's the name "Ethan" made out of invisible blocks).
Trivia
- The reason that it says the name "Ethan" in the sky because a five year old named Ethan from Texas loved to draw Angry Birds levels and he emailed Rovio, after drawing one. Rovio loved it so much, they made one almost exactly like his drawing and placed his name in the sky if you zoom out.