Level S-10 is the last Space Egg Level in Utopia. To unlock this level, you must 3-starring from level 4-21 to 4-30.
This level is chaos and a bit challenging to complete.
Throw the first space egg up so that it skims the leftmost fat pig’s bubble (line up the guide right at the bubble’s edge). The goal is to pop it the bubble without hitting the pig. This way the space egg slows, but keeps moving forward. Now detonate the egg right in front of the tiny asteroid. If you do detonate at the right angle the asteroid will fly through the area devoid of pigs and hit the TNT on the far right. This explosion can finish off the level.