Cosmic Crystals 7-15 is the fifteenth level in Cosmic Crystals.The objective of level 7-15 is to use the birds to eliminate all the pigs. Get at least 150,000 points for 3 stars.
This level looks hard, but it is very easy if you make the chain reaction.
Send the first Blue Birds for the two southern asteroids, splitting to also nudge the rocket nearby. The domino effect of massive implosions can easily clear the level. For some extra points, use another Blue Birds for the cluster of gems on the easternmost planet.