"The creatures are very playable - my 6 year girl old hasn't stopped since the first one was built. Did the set all on her own, took about 4 hours. One of the most playable sets we have, and suitcase "house" is very cool too. I suspect they like it so much is that the creatures are so big - easy to fly around the house - and that they are are not fragile, so 3 year old fingers won't immediately destroy them."