Version Alpha 1

A tactical board game for two players. Copyright 2000, McRey B. Moyer
Secret Doors Web Press,

The Game

Miners and horrifying ghost beetles vie for control of Demon Mine, a collapsed tunnel complex on a hostile alien world.

The Story

Human miners established Demon Mine, searching for precious ignium on a fiery, hostile planet isolated from civilization. A tunnel accident breached the armor of one miner, exposing him to the searing air of Demon Mine, and to a virus that transformed him into a massive, vicious white ghost beetle in a matter of seconds, perfectly adapted for the hot tunnels… and completely inhuman.

The miners soon discovered that their tunnels were saturated with the hostile virus. Every time the beetle attacked a miner and breached his armor, the miner was infected instantly, transformed into a ghost beetle. Overwhelmed by the powerful ghost beetles, a group of four miners rushed into the tunnels to trigger a radiation bomb designed to wipe out the virus and the beetles. Unfortunately, the team was buried alive inside the mine, and some of the terrible white beetles survived.

With two years away from rescue, and fearing the beetles would eventually come to their surface camp, the last few remaining miners had no choice but to return to the collapsed mine to rescue their four companions. The virus is wiped out in the tunnels, but the beetles can still inject it into unconscious miners with their fragile ovipositors.

So the battle begins in earnest, man versus insectoid, digger versus digger.

The Miners

These are strong individualists, space miners who have left civilization to seek riches in the most hostile reaches of the galaxy. Each miner is equipped with an armored, mechanized suit with its own internal environment to fight the intense heat of Demon Mine, and a powerful a pneumatic pick. A rock sounder, and a compass attuned to the planet’s magnetic field help the miner navigate the tunnels.

The Ghost Beetles

Mindless, palid monstrosities, the ghost beetles are driven only to survive and to kill. They have powerful pincers to attack their prey, and the consume human flesh in bloody chunks. Air wheezes through ventilation channels that keep the beetles cool in Demon Mine, and their thick carapace protects them from injury as they scuttle through the mine on powerful armored tearing limbs. The miners believe the ghost beetles have organs to sense magnetic fields and vibration in the tunnels… but biology isn’t foremost in the miners’ thoughts.

Game Components

Demon Mine tiles: one-and-a-half-inch square tiles, printed onto heavy cardstock. Get the file in three pages: tile page 1, tile page 2, tile page 3.

Dice: two six-sided dice. The regular cubes from your Monopoly game will do. More might be helpful in big combats.

Sixteen pawns: sixteen playing pieces, in two easily distinguished groups of eight. Chess pieces are best, checkers will do, and othello pieces aren’t bad. Pennies and nickels will even do in a pinch. You just need to be able to tell one group from the other.

Chess board: optionally, a chess board is very helpful for laying out the first part of the grid.

Play Areas

Demon Mine requires a fair amount of space to play.

The draw pile: a stack of unused tiles, face down. Unused pawns, four for each player, should be placed near the draw pile as well.

The hand: each player has a hand of tiles which he or she may see, but his or her opponent may not. The hand is pretty much the same as a hand of cards in, say, poker. When a player ends his or her turn, his or her hand must not have more than three tiles. Each player will start with four reserve pawns that will be played on the player’s first four turns, and these should be held with the tiles in the hand.

The grid: a theoretically infinite, imaginary playing space, made up of one-and-a-half-inch squares. Pawns and tiles are considered to be in play once they’re played onto the grid. It may be helpful to agree with your opponent to limit the grid’s space to the playing space available, and to define it with a good-sized chess board.

The pit: a discard area for tiles that leave a players hand without being used. Tiles in the pit must remain face down until you choose to draw one. It doesn’t matter who put a tile into the pit, either play can draw any tile in the pit. Neither player may move tiles once they’re in the pit, except when drawing a tile from the pit. Tiles placed into the pit must not touch one another. You’ll have to work with your opponent to make sure the pit doesn’t interfere with tiles on the grid. You’ll need a good amount of space to keep things from getting crowded.

The discard pile: you’ll need a more traditional discard pile for tiles that leave play. You can place pawns in the same general area when they leave play.

The Object

The object of the game is to destroy all of your opponent’s pawns. As you dig through Demon Mine, you’ll find miners trapped in the rubble who will join your forces. These extra forces will be critical to your victory.

Getting Started

Pick out the MINE ENTRANCE tile and the GHOST BEETLE HIVE tile. Place them on a diagonal line on the grid, with exactly seven squares between them. That is, as though they were in opposite corners of a chess board. This is where an actual chess board will come in handy.

Mix up the rest of the Demon Mine tiles, and place them face down in a single stack. Both players will draw from this stack.

Arrange the Pit. The Pit is an area where unused tiles will be placed face down, not touching each other, and may take up quite a bit of space. It shouldn’t overlap with tunnel tiles on the grid.

Decide who will go first. Each player rolls one die. Whichever player rolls highest gets to choose who goes first. Re-roll ties.

The player who lost the roll gets to choose to play the miners (typically, the black pawns) or the ghost beetles (the white pawns). Each player takes four of the appropriate color pawns as reserve pawns. They don’t go onto the grid yet. The other four of each set are set aside, near the draw pile.

The Turn

Players alternate turns. Play your turn in the following sequence:

  1. New pawns enter. If you any of your four reserve pawns is not on the board, you must place one on the MINE ENTRACE (if you’re playing the miners) or on the GHOST BEETLE HIVE (if you’re playing the ghost beetles).
  2. Draw one tile. You may draw one tile into your hand from the draw pile or from the pit. During your turn, you may hold more than three tiles in your hand.
  3. Move or burrow. Each of your pawns may burrow (see Burrowing) into one adjacent square, may move once or twice into adjacent squares (see Movement), or may remain in place. As each pawn burrows, you may draw an extra tile from the draw pile or from the pit. If one or more of your pawns neither burrows nor moves, you may draw one tile from the draw pile or pit after all pawns have moved or burrowed.
  4. Play events. Play up to one event tile (see Events).
  5. Move overflows. If more than two pawns occupy any given square on the grid at this point, your opponent must move one pawn at a time into an adjacent square, if possible, following the normal rules of movement. Your opponent may choose the order in which “overflow” pawns move, and may even move them into squares occupied by too many other pawns or by his or her own pawns.
  6. Discard tiles over three. If you have more than three tiles in your hand, discard them one at a time in the pit. Continue to discard until you have no more than three tiles. You may discard to fewer than three tiles if you’d like. Signal your opponent when you’re finished.


Each pawn may move into one or two adjacent squares in a turn. Pawns may only move onto or through tunnel tiles, and only through sides connected by open tunnels.


Instead of moving, any pawn may burrow once per turn. Choose a tunnel tile from your hand, and place it such that an open tunnel connects with an open tunnel in the pawn’s current square. Then you must place the burrowing pawn into the new tunnel tile.

A TUNNEL COLLAPSE also counts as burrowing, but is played differently from a tunnel tile. When you play a TUNNEL COLLAPSE, move the burrowing pawn into an adjacent tunnel, following the normal rules of movement. All other pawns are also allowed to move into an adjacent tunnel. Then remove the tunnel tile originally occupied by the burrowing pawn. Remove the TUNNEL COLLAPSE tile from play, along with the destroyed tunnel tile. If it’s ever possible for enemy pawns to be in the square when a TUNNEL COLLAPSE is played, the are also moved to adjacent squares, by the player who played the TUNNEL COLLAPSE tile. If a tunnel is destroyed by a TUNNEL COLLAPSE tile and the pawns can’t legally move out of the space, the pawns are removed from play.

Burrowing is normally used to replace empty tiles, but it may be used to replace tunnel tiles. Any tunnel tile may replace another if the new tile has an open space corresponding to each open side of the old tile. That is, the new tile must “fit over” the old tile. Neither tunnel tiles nor TUNNEL COLLAPSE tiles may replace or destroy the MINE ENTRANCE or the GHOST BEETLE HIVE. Any tunnel tile may replace a LODESTONE tile.


Each player may play one event tile per turn. Both MINER tiles and LODESTONE tiles are events.

MINER: You recover an unconscious miner. If you’re playing miners, you can rouse him. If you’re playing ghost beetles, you can inject his body with the virus. During phase 4 of your turn, you may place a new pawn (that’s what the four pawns were set aside for earlier) in any new tunnel tile created by your pawns this turn. You must remove the MINER tile from play.

LODESTONE: Place the LODESTONE tile in any square on the grid. As long as the LODESTONE remains on the grid, any tunnel tile placed by either player within two squares of the LODESTONE tile is oriented by that player’s opponent. The original player still gets to choose on which square the tile is place, but his or her opponent decides which direction it faces, as long as it’s still a legal move for that burrowing pawn. Distance from the LODESTONE tile is measured as a moving pawn. Pawns may not move into the LODESTONE square, but pawns may burrow through it. If any pawn burrows through the LODESTONE, remove the LODESTONE from play.


Combat may take place any time pawns are eligible for combat. Be sure to check for combat conditions constantly during phases 1, 3, 4, and 5 of each turn, as these are the phases in which pawns can be moved or added to the grid.

Whenever your pawn is in the same square as an opponent’s pawn, the pawns will engage in combat. Players may move pawns simultaneously to involve more pawns in the combat. In this case, all pawns in the square, yours and your opponents, must engage in combat.

If, on your turn, your pawns are adjacent to your opponent’s pawns, and there is open tunnel between them, you may choose for the pawns to engage in combat with them. Both you and your opponent may choose which pawns engage in combat.

All of your pawns in combat must be in a single square. All of your opponent’s pawns in combat must be in a single square.

Roll one die for each of your pawns engaged in the combat. Your opponent does the same for each of his or her pawns. The player who gets the highest roll wins, and the loser must remove one of his or her own pawns engaged in the combat from play. If both players’ units were in the same square, the loser must move all pawns into adjacent squares (they can be split up) not occupied by enemy pawns, if possible, following the normal rules of movement. If the pawns in combat were in adjacent squares, the loser may choose to move any or all of his pawns into squares not occupied by enemy pawns, if possible, following the normal rules of movement. The combat ends.

If both players’ highest dice were equal, nothing happens. Nobody has to remove any pawns, and nobody gets to move any. Of course, the pawns may engage in combat again.

Pawns not engaged in combat can’t be moved when a player loses a combat, even if they were in the same square.


A player wins when his or her opponent is eliminated. Neither player may be eliminated until all four starting pawns from each player have been placed on the grid. After that, a player is eliminated when his or her turn ends with none of his or her pawns on the grid.


Tile tweaking. The most basic variants come from adjusting the proportions of tiles in the set. Add more TUNNEL COLLAPSE tiles to make things more dynamic, add more LODESTONE tiles for more outright chaos. More MINER tiles for a longer game, or cut one or two for a shorter game. Put in mostly elbow tiles to make Demon Mine more limiting and deadly, with lots of long, uninterrupted stretches of tunnel.

Small grid. Limit the game to a single chess board for a short, bloody game.

Four-player. You’ll need another two distinct sets of pawns, another MINE ENTRANCE tile and another GHOST BEETLE HIVE tile. You may choose to have more of the other kinds of tiles, too. Two players play rival mining crews, and two players play different strains of ghost beetle. Place two GHOST BEETLE HIVE tiles at opposite corners of the “chess board” portion of the grid, and the MINE ENTRANCE tiles at the other two oppose corners. Players attack each other as if they are opponents, even if they’re of the same species … so a miner pawn in a square with the other player’s miner must engage in combat. The miners win when all ghost beetles are eliminated, and the ghost beetles win when all miners are eliminated.

Othello. Use othello pieces in play, the ones that’re black on one side and white on the other. The miners have the cure for the ghost beetle virus, and the ghost beetles have the ability to infect active miners. When a player loses a combat, he or she turns over a pawn rather than removing it from play.

Homebrew tiles. Make up your own events and burrowing tiles to flavor the game in any way you can imagine.

by McRey "Mac" Moyer
Secre Doors Web Press