Let the mob pass a cWorld instance to the pathfinder via a special function that will be called whenever the mob's world changes (mob goes through a portal); this function should also reset all the pathfinding progress so far etc.
EDIT: Note that you can't pass the cWorld instance through the constructor, because at the time of construction the mob has no world assigned to it yet. The world is assigned in the cMonster::Initialize() function.
EDIT: Note that you can't pass the cWorld instance through the constructor, because at the time of construction the mob has no world assigned to it yet. The world is assigned in the cMonster::Initialize() function.