Working Angry Birds cake for 4 year old twins Tyler and Damien.
Birds and Pigs are all edible made of fondant (but let the kids know that they would not taste good). The Building structures are Rice Krispy Treats covered in fondant. The slingshot is a toy, mounted in a mound of Rice Krispy Treats and covered in Chocolate Fondant.
I added Tylose powder to firm the fondant. The pigs, birds and Building pieces were very hard and able to withstand multiple rounds of play.