Take a blank sheet of paper to be your dungeon map. Draw a rough line across the page the long way, a bit less than two inches from the edge. This is the ground surface. Everything in the narrow area is aboveground; everything below it is underground.
In pencil, write the numbers 1-6 down each narrow side of the page evenly spaced in the underground area.
Roll a d8 on top of the dungeon map. If the die lands off the page, re-roll it so it lands on the page. Consult the appropriate entry in the Primordial Events table for instructions. Repeat this process three times.
|1||Mithral: Drop two dice on the map. At the point where each die falls, draw a triangle about half a finger on each side pointing towards the nearest corner of the map. Label the triangle as mithral ore.|
|2-3||Natural Caverns: Roll another d6 on the map. In pencil, draw a natural cavern about 1 bead in size at its landing point. Consult the Natural Caverns table. Continue to do this until you roll a 6 or have 6 caves.|
|4||Gold Vein: Roll two d6s. In red, draw a line from the first number on the left to the second number on the right. This is an underground vein of gold-bearing rock cave.|
|5||Cave Complex: In pencil, draw three bead-sized natural caves near where the die landed. Connect them to each other with pencil lines. Place a in each cave. These are primordial beasts. If any of the caves is within a half finger of the surface, connect it to the surface with a pencil line. Beasts fight as wandering monsters (see the Age of Monsters).|
|6||Underground River: Roll a d6. You will start an underground river from that number on the left side of the page. Roll another d6 and follow the instructions in the Underground River table. Continue to roll on that table until the river leaves the page or reaches the surface. If the river reaches the surface, end it with a lake or a sinkhole.|
|7||Ancient Wyrm: Draw a natural cavern 2 beads in size at the point where the die landed and place in it 1 for the wyrm and 1 for its treasure. Make up a name for the ancient wyrm that lives therein and write it on the map. During the Age of Civilization, any civilization that encounters the wyrm cave loses 1 to the wyrm. During the Age of Monsters, the wyrm becomes an alpha predator.|
|8||Roll a d6. On a 6, make up your own primordial event or choose one from this table. Otherwise, roll on the natural disasters table later in these rules.|
|1-3||The river moves 1 finger horizontally across the page.|
|4-5||The river changes angle sloping upwards while continuing across the page.|
|6-7||The river changes angle sloping downwards while continuing across the page.|
|8-9||The river moves 1 finger horizontally across the page, with a natural cave 1 bead in diameter in the middle of it. If the river is within 1 thumb of the surface, draw a sinkhole connecting this cave to the surface.|
|10||Waterfall, dropping 1 half finger straight down.|
If an underground river touches the surface, it ends in a lake.