In DragonVale for the iPhone and iPad, the Butterfly Dragon is a limited dragon that is only available around the last half of spring in the upper hemisphere, which is around the last three weeks of May through the first three weeks of June.
To get a Butterfly Dragon, you need to breed an Air type or Air Hybrid with a Firefly Dragon (Firefly = Fire + Lightning)
Check out my DragonVale Breeding Guide for more dragon breeding combinations.
