Pig Bang 1-18

Pig Bang 1-18 is the 18th level of Pig Bang.Pig Bang level 1-18 is deceivingly tricky.

Difficulty
You need to use explosion to push asteroids to destroy the fortress, it's a hard work.

Strategy
A good trajectory of the first Black Bird is just above the small asteroid at the edge of the sling-path. It may take another Black Bird or two, but the asteroids should eventually crush the pig on ice.

Walkthrough
http://www.angrybirdsnest.com/angry-birds-space-pig-bang-level-1-18-walkthrough/