The Runes of Sorcery - Jane Welch

The adventure begins… Whoever holds the Egg controls the ancient animals of power: kraken, wyvern, and dragon. Whoever cracks the Egg unleashes these monsters on the world, unrestrained and beyond the control of anyone alive… Three young Torra Altans, Caspar, Brid, and Hal, are closing in on the immemorial hiding place of the Egg. Strange wild beasts that sense their purpose follow close behind. From Yew Wood to Lake of Tears, spices and enemies pursue them. The Mother Goddess has promised that once the Egg is brought to their ancient home in the North, the starving hordes of Vaalakans besieging the castle will be driven back. But creatures of legend desire to be real, and time is running out.