After saving his clan from saber-toothed tigers, Lug the caveboy has become a hero. The only problem: between the nightmares and his sudden skittishness around animals, he doesn't feel like much of a hero. But now he and his friends, Stony and Echo, have even bigger problems. A giant glacier is rolling toward their village--faster than any ordinary mass of ice should move--and it's on course to crush the whole settlement Maybe Blast, the mysterious...