Infinite Dungeon
The Challenge Dungeon is an infinite dungeon that gets progressively harder the further you get. The Challenge Dungeon is located North West of Bala (1 map-tile up and then 1 map-tile left of Bala). Every 5 levels there is a 'Boss' guarding the stairs to the next level. The amount of enemies you find in each room of a level can vary but goes in a simple pattern. 'Small' being 1 per room, 'Medium' being 2-3 per room and 'Large' being 3-5 per room.
Throughout the Challenge Dungeon you will come across boxes/crates/chests that can be opened for a little gold and sometimes a helpful item. There is also a random chance of finding a Monk while exploring. These NPCs will sell you useful provisions such as food, potions and Town Portal scrolls. It's worth noting that there is no 'Gold Allowance' within the Infinite Dungeon but you cannot leave with your gold. You can however, leave with the items you find/purchase within the Challenge Dungeon, so it is advised that you invest all gold in the Monk's provisions.