The Secret of the Swamp King (The Wilderking Trilogy)

As book two opens, Aidan is living in the court of King Darrow. He has become best friends with Darrow's son Steren, and he enjoys great favor among the courtiers. But King Darrow's suspicion is growing and his insecurity causes him to hate the young man who saved his kingdom. Concerned about his king's spiral into ever-darker moods, Aidan asks what he can do to help. Darrow sends him on an imposible adventure to the recesses of Feechiefen Swamp, thinking he is sending Aidan to his death. Afterall, no Corenwalder has ever returned from Feechiefen alive. But Aidan's fate is not sealed yet for Aidan has allies among the feechiefolk who know him as the hero Pantherbane.