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Cave Mining


Assignment: Design a dice game.


The big lesson I learned from this assignment is that sometimes, you really need to say no to an idea. The game presented here is not the one I initially had my heart set on. However, it still ended up being a great deal of fun and ultimately more rewarding.


I tried incredibly hard to get my first idea to work, but in the end I was just better off setting it aside.


Final Ruleset

What is included:
Game Board
Dice: d4, d6, d8, d12, d20, d100 (d100 in the form of two d10s)
3 player markers, 3 base markers


To be played by 2-3 people.


There’s money to be found in them thar caves!  Gold, gems, oil, the works!  But you’ll need to get it first!  Dig down for treasure while avoiding cave-ins and sabotaging your opponents!  Be the first to 150 treasure points to win!


Each layer in Cave Mining has an associated treasure die and risk percentage. 


On the game board, the treasure die is displayed in yellow with a red border.  That is the die associated with that layer of the cave (from d4 to d100).


The risk percentage is in red with a black border.  That is the chance that the cavern will cave-in when digging in it (5% = a five percent risk of cave-in).


A cave-in roll is the term for rolling to see if a given layer caves in.  For a layer to cave in, you must roll (on a d100) less than or equal to the risk percentage. 


Every player has a figure to represent their digger and their base camp.  The base-camp is mostly intended to represent the deepest that a digger has successfully mined.


Players initially start off the board, dig to get to the 5% risk percentage layer, and then work their way down to the 70% layer.


Players have the chance to dig, get treasure, and sabotage each turn.  The turn breakdown for each player is on the following page.


  1. “The Mine is Unsteady!” – (The Rolling Cave-in Rule) At the beginning of each turn, do a cave-in roll for the current layer that the player’s base camp is at. 
    1. If a cave in happens, move the base camp up to the previous layer, and do a cave-in roll again.  Keep doing this until a cave-in doesn’t happen.  Place the base camp and the digger on the safe layer.  If the player was sabotaged before their last turn, go to step 2.  Otherwise, go to step 3. 
    2. If the cave-in doesn’t happen, simply go to step 2.
  1. “What Now, Sir?” – The player chooses whether or not they want to dig, or look for treasure.
    1. “Digging?  Righto.” – If the player chooses to dig, roll the cave-in roll for the layer they are going to.  If no cave-in happens, go back to step 2.  If a cave-in happens, move the digger to the base-camp layer.  Go to step 4.
    2. “Gold!  And it’s all mine!” – If the player chooses to look for treasure, move the base camp to the layer with the digger.  Go to step 3
  1. “Sabotage!” – You know you want to do it.  If an opponent has their digger and base camp on the same level that you are currently at, you may forego getting a treasure die for this layer to have them perform the Rolling Cave-in Rule.  This works just like the sabotaged player having to perform Step 1, but not proceeding to any following steps.  Afterwards, go to Step 4.  (Note: if the current player just suffered from their own Rolling Cave-in, they cannot sabotage.  They are too busy trying to repair their mine!).
  2. “I see something shiny!” – Collect treasure die for each layer above your base camp.  If you didn’t sabotage this turn, you may also collect a treasure die from the layer containing your base camp.  Roll them, and add the total to your treasure points.  Go to Step 5.
  3. “We’re Rich!” – If you have more than 150 points left, and if all players have gone the same number of turns, you win.  If all players have not gone the same number of turns, they may execute their last turns now.  When all players have gone the same number of turns, the player with the highest score wins.


For those without a board, the treasure die and risk percentage for each layer are as follows:


            Layer Name                 Treasure Die                 Risk Percentage
            Spare Change Valley                D4                               5%
            Dino Bone Bedrock                  D6                               15%                
            Sedimentary Silver                    D8                               25%
            Golden Ground             D12                               35%
            Diamond Hotspot                     D20                             50%
            The Priceless Core                   D100                           70%

Click on this to download the document describing the design process,
along with initial rules and playtest data.