Save the girl. Beat the dungeon. Get epic loot. 
After a few minor setbacks, Aaron and Crash find themselves all alone in the World of Ruul with only one chance at survival, finding the legendary soulstones before the maelstrom's forces eat them and their friends. 
Worse, the only way to get strong enough to save their friends is to enter a dungeon no one's ever beaten before, defeat the four elemental bosses who reside inside, and shatter the massive statue trapping them inside. 
Sure, it might be impossible, but if it were easy, everyone would have done it, right?