'A cold wind whistles... You have been traveling for long, and the last time you saw anyone, was when you were saying goodbye. The wars and feudal disputes of Cronos have ravaged any semblance of peace, but you walk amidst the ruin searching for it none the less. Climbing through a mountain pass, you come upon a village, though abandoned....' HellTown is a custom WAD for Hexen. There is no hub system. It is one megaWAD, that interprets as zones. You will need to travel throughout the zones and return to ones you've visited before once you've obtained the proper pieces to the puzzles to progress. Journals and other documents are keys of information that reveal the story and hint at the solutions. The game was made without difference in difficulty regarding number of monsters, the game progressively becomes more challenging as you near it's end.
