How to fight The Dead King in Hexplore It Valley of the Dead King

About HEXplore It: The Valley of the Dead King, from BoardGameGeek:

HEXplore It is a hero building adventure board game. Enter a realm teeming with fantasy creatures, heroes and villains. Select your hero by combining two character options: your Role and Race. Your Role is your profession and your Race is your heritage and species. This combination drives your Hero's strengths, weaknesses and defines their special abilities. You'll use dry erase markers to keep track of your hero's strength. Travel across the map earning power ups by completing quests and battling opponents of several different types. Move carefully to avoid multiple dangers and travel from city to city, visiting shrines and ruins along the way. Gain power quickly, for the Dead King also moves... He takes away your cities as you play the game. For each city he destroys, he gains more power. The object of HEXplore It is to power up your heroes as quickly as possible, to eventually defeat the Dead King himself. The game is won if you confront and defeat him, bringing light back to the Valley.