How to Host a Dungeon is a solo dungeon-building game/toy that allows you to evolve a dungeon through four "ages": the primordial age, when the land is created; the age of civilization, when an ancient people carve the land until some extinction event; the age of monsters, when numerous groups fight for the land; and the age of villainy, when a powerful force attempts to take over the land.
During the primordial age, you roll on some tables to fill the underground with features like caves, rivers and veins of gold and minerals. Here's the result of this first age, in which I rolled a cave complex and two sets of natural caverns. In this age the dark green circles are primordial monsters hidden in the dark and the light green ones are minerals and gemstones. I'm not sure if I should have stacked the minerals like that but in the end it worked.
I selected the dwarven civilization for the second age of my dungeon (in the demo version there are two options: dwarves and dark elves.) Since I didn't have many minerals, I had to generate a gold vein. This civilization starts with a main mining shaft, one mine chamber and one barracks. Here's the view after the first complete year, with a new mining chamber, barracks and treasure room. The red line marks the gold vein.
Eventually the dwarf mining expanded to the left until reaching the cavern with gemstones. This sudden increase in wealth prompted a populational boom in the Grizzlybeards stronghold, leading to the foundation of the underground city of Rockhaven. The dwarves continued their exploits but eventually, delved too deep and were decimated by things that lurk in the dark, finishing the Age of Civilization.
Years later, a "fallen star" crashed near the abandoned dwarven stronghold, opening a large crater and new caves and tunnels. Monsters started inhabiting the old tunnels and humans built a castle near the ancient mining shaft, starting the Age of Monsters. Besides the surface dwellers of Castle Leroy, there were three groups at the beginning of this age: a settlement of duergar, a tribe of cave giants and the dreaded ogre magi, occupying the ruins of the underground city.
Right at the beginning of the Age of Monsters, a group of adventurers arrived and started exploring the tunnels. One of the adventurers, a valiant paladin, died in a skirmish with the cave giants, although the monsters were eliminated. Another adventurer lost her life in an ambush by the duergar and despite their losses, the adventurers kept exploring... until they found the ogre magi. None of them survived the encounter and the ogres kept all the loot from the adventurers. The same ogre magi would then find the ancient dwarven treasure room and their large pile of treasure would soon attract the attention of other creatures. This ended the Age of Monsters, and the Age of Villainy began. I rolled the Thought Lord Cult as the villain. These are mind-controlling creatures that try to dominate all the other groups in the dungeon and above.
The purple markers are "control markers" that indicate that the group is under influence of their Mind Pool. In the first year of the Age of Villainy, the thought lords managed to infiltrate the ogre magi, which would provide them with slaves and gold. In this same year, a couple of adventurers entered the dungeon but fell prey to the duergar.
In the following years the thought lords infiltrated the duergar but failed to take control of the humans at Castle Leroy. One party of adventurers killed the ogre magi and even faced the thought lords but fled after considering their losses and the loot they had obtained. The city of Starlight was founded after the growth of the human population and eventually, another group of adventurers managed to defeat the Thought Lord Cult, although at the cost of the life of a divine priest. Thus ended the Age of Villainy; here is the final map:
Total playing time: 2 and a half hours. Note: some details like the adventurer types were added to the narrative as I typed this post, they were not generated by the system.
The resulting dungeon, and its accompanying history, may be used in a classic dungeon exploration RPG as suggested in the appendix of the book. The idea is not to use the map as is but to refer to it as a source of major landmarks (like the duergar complex or the underground city of Rockhaven in my map) and how they are connected.
How to Host a Dungeon is a fun solo activity. It is also an involved process, especially when the monster groups appear. The rules are clear but there's quite a bit left to interpretation, allowing the player to adjust the results. I think that playing on the computer using some kind of graphics software that supports layers is ideal. There's some tweaking between the ages that I think would be hard to do on paper.