MINE-SHAFT GAPBy Matthew Nadelhaft

Mine-Shaft Gap simulates a battle for resources on, above, and under the surface of a lifeless but treacherous planetoid. Players must seek out valuable metals and fuel materials and mine them, using the materials to feed their home planets, and inch closer to victory, while at the same time allocating resources to maintain or strengthen their armed forces and fortifications. Drill tanks tunnel beneath the surface of the planet while drilling stations pound away from above. Drilling stations are faster and more efficient, but are vulnerable to attack from above and even capture by enemy troops. But tunnels can cave in… And market forces are unpredictable. The resource making your planet rich today might be better off greasing the treads of your tanks tomorrow!

Components:

The game takes place on two maps – one representing ground level and above, the other representing underground terrain. The rules differ slightly depending upon the map on which action occurs. At the beginning of the game, the subterranean map is unmarked: it is solid. As the game progresses, units will drill beneath the surface of the planet, creating tunnels through which they and other units can explore the sub-surface, mining for riches and engaging each other in combat. Each map parallels the other, in that each hex on one map represents the same coordinates, just at a radically different elevation (above or below ground) on the other map. Maps are labeled in columns and rows so that it is possible to find corresponding hexes quickly. Hex B4 on the surface map is considered to be directly above hex B4 on the subterranean map, and so on. It is recommended that a new subterranean map be printed out for each game, so that it can be marked throughout the game and discarded at the end.

Counters represent structures, mobile units such as drill tanks, transport vehicles, hovertanks, missile launchers, atmo-craft, and squads of infantry with jump-jet powered armour; in addition to command posts; drilling stations; extracted resources; and rubble. They are printed with varying information. Resource counters show the type and quantity of resource with a letter and number. Units are printed with a movement type, attack strength, range, defense strength, and movement points, as shown in the following diagram:

Movement value and type Indicates mining capability

Unit silhouette

Attack strength Range Defense strength

6T M

2 2 2

Set Up:

Each player chooses an edge of the map and one set of counters. Allocate each player one-hundred resource points of metal ore. These resource points must be used to purchase starting forces; none can be spent on victory points. Some may be saved to use on subsequent turns, however, to purchase units and orbital scans or bombardments (it should be simple enough to keep these starting resource points, which cannot be used for the purpose of purchasing victory points, separate from the resource points accumulated later in the game, which can be used to purchase victory points. Those resource points will be collected in the form of numbered counters, while the starting allocation of resource points can be kept track of on paper). The cost of a unit in metal-ore resource points is equal to its attack strength plus its movement value, with the exception of command posts and drilling stations, which will be discussed later. Each player receives a command center counter at no cost to begin the game. Players set up simultaneously. If they wish to, they may set up with their counters face down, and then flip them face up to begin the game. Place your command centre in any clear hex, at any elevation, within four hexes of your edge of the surface-level map. Your starting force must be placed, obeying stacking restrictions, within a four-hex radius of your command post, including the hex occupied by the post. All units begin the game at surface level.

Decide on the victory point total that will end the game. Try fifteen points for a basic game, or thirty points for a long game. Determine who will be the first player: that player takes the first turn throughout the game.

Shuffle together the resource counters and dummy counters, face down. Roll to determine which set of resource symbols will be used in this game: place one counter, face down, on each marked resource hex of the indicated type on the subterranean map. Put aside the remaining resource counters for use as resource chits throughout the game.

Die Roll: Resource Symbol Used:1-2 s3-4 S5-6 T

Turn Sequence:

Mine-Shaft Gap is played in turns which are divided into a series of phases. Each player completes all the phases of his or her turn, in order, before the next player does the same. The phases of a complete turn, in sequence, are:

Orbital Scanning PhaseBombardment PhaseResource Extraction PhaseResource Allocation PhaseMovement/Tunneling PhaseCombat Phase

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End Phase

Orbital Scanning Phase:

At the beginning of each player’s turn, he or she may spend five resource points (of any type) in order to have spy satellites perform enhanced topographic scanning of a region of the map. Pick any face-down resource counter and examine it. You may make notes; Mine-Shaft Gap is a game of tactics, not memory. Orbital scanning can only be performed once each turn.

Bombardment Phase:

For another ten resource points of any type, a player may order a satellite strike, using missiles and lasers, upon any hex. By bombarding a mountainous hex with a barrage of powerful explosives and industrial lasers, it can be converted into a crater hex (see rules on terrain types, following). Place the appropriate terrain counter on the hex; for the rest of the game, treat this hex as a crater, not a mountain hex.

Units within bombarded hexes are subject to attack. Treat satellite bombardment as an attack upon all units in the target hex with an attack strength of twenty, using the standard combat rules that follow later. Note that units in hexes of any terrain type may be attacked in this manner. In such a case, precision bombardment is used, and no damage is done to the hex, unless the player who called for the bombardment wishes. Any hex can be turned into a crater hex in this manner – even an empty, clear hex with no units in it, perhaps for the purpose of creating a strategic “trench”.

Resource Extraction Phase:

Should any player have uncontested occupancy of a resource hex (see following), he or she may extract resources. The resource counter occupying the hex has printed on it a number representing how much of that resource – represented in “points” – can be extracted each turn. As long as a player has at least one mining unit (designated by the letter M printed on its upper left corner) in or (in the case of drilling stations, above) the resource hex, he or she may extract the number of points printed on the resource counter. Since the time-frame of this game is relatively short, treat each resource hex as having infinite resources: the maximum number of resource points may be extracted from it each turn, as long as conditions for uncontested occupancy are met. Theoretically, of course, the node would eventually be exhausted. To represent extracting resources, take a resource chit of the appropriate type and number (make additional chits as necessary). If the resource was extracted from a station, the resource chit goes directly into your possession – i.e.: it is ready for use in the next phase. If the resource was extracted via the subterranean map, the chit must be placed on any vehicular counter (any counter using wheeled, track, or hover movement) in the resource hex or in a tunnel hex adjacent to the resource hex, for transportation to any command post or centre. A vehicle can transport an unlimited number of resource chits following regular movement rules. Resource chits can be “handed off” from a vehicular unit to an adjacent vehicular unit, provided that a:

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The receiving vehicular unit is in clear terrain or a tunnel hex, has not moved this turn, and is not damaged or within an enemy zone of control and b: the vehicular unit that hands off the resource chit(s) thereupon ends its movement. Once these chits are received at a command location, they are available for use. Should a transporting vehicle be destroyed, any chits it carried are left in the hex in which it was destroyed, and may be picked up by any friendly or enemy vehicle unit, at no cost in movement points, that passes through the hex.

Uncontested Occupancy:

A player has uncontested occupancy of a resource hex when at least one of his or her units occupies the hex, or a drilling station occupies the corresponding, ground-level hex, and none of these units are within the Zone of Control (see Movement rules, following) of any enemy unit.

Resource Allocation:

Resources come in two types: metal ores and fissionable materials. Resources are represented by numbered chits, distinguished by the initial M for metal ores and F for fissionable materials. Resources are used to build units and fortifications and to purchase victory points. Each turn, market conditions without the players’ control determine how many resource points are required to buy each victory point by rolling on the following chart. These results are obtained by the first player at the beginning of his or her resource allocation phase, but hold true for both players’ turns. They will be rolled for again the next time the first player reaches the Resource Allocation phase. Fractions of victory points can not be purchased, but unused resources are saved for subsequent turns. Victory point totals may not be kept secret and must be announced each time victory points are purchased.

Market Fluctuation Table:

Die Roll: Victory Point Cost:1 One metal ore resource point + one fissionable material

resource point2 Two fissionable material resource points3 Two fissionable material resource points + one metal ore

resource point4 Three fissionable material resource points5 Two metal ore resource points + one fissionable material

resource point6 Two metal ore resource points + two fissionable material

resource points

Purchasing Units:

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Units are purchased as they were at the beginning of the game, at the cost of their attack strength plus movement value in metal-ore resource points.

Special Units:

Drilling Stations: Drilling stations are immobile and can not attack. They do not exert zones of control. Their cost depends upon their location. The basic cost of a drilling station is five resource points, plus one resource point per level of elevation of the station. For instance, a drilling station built on an elevation four hex costs nine resource points. Obviously, the further that the station must drill, the larger and more powerful it must be and the more it will cost. Drilling stations do not possess defense strengths or affect the defense strength of units stacked with them, and they do count for stacking purposes, but they must be attacked as part of a stack. If all the units in the stack are destroyed, the drilling station can be destroyed or left unoccupied at the defending player’s option. An unoccupied drilling station can be captured by any non-flying enemy unit moving into the same hex. Replace the drilling station with a counter of the appropriate colour to signify its capture.

Command Posts: Command posts cost ten resource points. A drilling station can be upgraded to a command post at a cost of five resource points and continues to function as a drilling station. Command posts, too, are immobile, and cannot attack. However, they do not count against stacking limitations and, in fact, double the stacking limit of the hex they occupy (the same is true of the command centre with which each player starts the game), generate zones of control, and counteract enemy zones of control. That is, enemy units adjacent to a command post do not exert zones of control. Units in the command post hex can continue extracting resources even if surrounded. Non-flying units cannot exit a command post through a hex occupied by an enemy unit. Units can attack from inside command posts. Command posts can be attacked along with any units inside them, and are destroyed or left unoccupied in the same manner as drilling stations. The command post provides no defense strength of its own, but doubles the defensive value of all units in its hex. An unoccupied command post has no defense value. Any non-flying enemy unit can enter a command post, taking possession of it. Replace the command post with a counter of the appropriate colour to signify its capture. The Command Centre follows the same stacking rules as command posts and also doubles the defense strength of units in the same hex, but has its own attack and defense strengths, as well; thus, it can not be captured. It can be destroyed, and new command centres cannot be built. Destroying a command centre does not end the game, but a player without a command centre cannot call for orbital scans or bombardments.

Unoccupied command posts or drilling stations are automatically destroyed by orbital bombardment. Because of their sophisticated ECM, command centres cannot be targeted by orbital bombardment.

Command posts and drilling stations can be built in any hex that is occupied by at least one friendly, non-flying unit, and is not currently within an enemy zone of control. All

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other units, when purchased, can enter the game in any friendly command post or center. Flying units are considered “grounded” until their first movement phase. While grounded these units count against ground-unit stacking limitations, can not attack and have a defense strength of one. Once a flying unit “takes off” (moves for the first time), it is considered airborne for the rest of the game, and operates at full capacity.

Movement:

Each mobile unit has a movement value, expressed in points, printed at the upper left-hand corner of its counter. Units move by spending movement points as they enter hexes. A unit may not spend more than its movement value, nor may movement points be saved for later turns, transferred to other units, etc. A player must move one unit at a time, and must finish moving the chosen unit before beginning to move another. Each turn, a player may move any number of his or her units, as long as no unit moves more than once. Non-flying units may not enter or pass through hexes containing enemy non-flying units.

Each mobile unit also has a Movement Type printed next to its movement value. A unit may have one – or more – of the following movement types:

W – WheelsT – TracksH – HoverF – FlyingJ – Jump Jet

Each hex costs a certain number of movement points to enter, depending on the movement type of the unit entering. The number of movement points it costs for a unit to enter a hex can be found on the following table. Hexes are printed with symbols designating their terrain type. A hex with no symbol in it is clear terrain – i.e.: a relatively level, rocky surface with no significant features. All hexes on the subterranean map are considered the same, for movement purposes – impassable rock and solid earth. The only units that may pass through these hexes are drill tanks, which may do so at a constant rate of two movement points per subterranean hex they enter. As they drill through each hex, they create tunnels – mark each hex through which a drill tank passes in any manner you see fit – with a blank counter, by pen or by pencil. All other mobile ground (non-flying) units can now pass through those hexes as if they were clear terrain. All hexes in the subterranean map are considered to be at the same elevation. Obviously, drill tanks begin the game on the ground-level map. They may enter the subterranean map on any movement phase by spending all of their movement points to create a tunnel opening. Place a tunnel-opening counter on the hex occupied by the drill tank, and move the tank to the correspondingly designated hex on the subterranean map. That subterranean hex is now the first hex in the drill tank’s new tunnel. Any non-flying unit can enter a tunnel through a tunnel-opening hex following normal movement rules regarding zones of control and the cost of entering the tunnel-opening hex. It costs one extra movement point to make the transition between surface and subterranean maps through a pre-existing opening. An underground drill tank may chose to surface on any turn by

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spending all of its movement points and creating a new tunnel opening on the surface-level map in the hex corresponding to its current subterranean location. The drill tank then moves to the tunnel-opening hex on the surface map.

Symbols on the subterranean map are purely for the purpose of resource distribution, and have no effect upon movement.

Movement: Terrain Type:Type:

(No symbol)=Clear: U=Rough: 5=Mountains: K=Crater:W 1 2 -- 3T 1 1 3 2H 1 1 -- 1F 1 1 1 1J 1 1 2 1

If a unit does not have enough movement points to enter a hex, it cannot do so on that turn. The symbol -- indicates that a hex of the indicated type cannot be entered by a unit with the indicated movement type.

In addition, each hex is a particular shade of grey, from white to black. The shade of a hex indicates its elevation. Elevation has no impact upon movement except when a unit changes elevation – i.e.: moves from a hex of one shade to a hex of another shade.

Low elevation: level 1

Basic elevation: level 2Raised elevation: level 3

High elevation: level 4

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For all except flying units, the difference in elevation level between the hex previously occupied and the hex being entered (always expressed as a positive number) is added to the terrain cost of entering the hex. For example, a unit with jump jet movement, going from a level 1 hex (note that it does not matter what terrain type the hex being exited is) into a level 2 rough terrain hex must pay 2 movement points. A wheeled unit making the same move would have to pay 3 movement points.

Transporting Troops:

A Utility Vehicle can transport one Jump Troop counter per turn. To do so, it must begin its movement stacked with the Jump Troop counter. As long as the vehicle and troop do not violate stacking limitations, the troop counter may be carried by the Utility Vehicle up to the vehicle’s full movement allowance. The vehicle must end its movement in the hex where the troop counter disembarks. Disembarking does not cost movement points for either counter. Troop counters can move under their own power before or after being transported in this manner (provided, of course, that they do not move more than once per turn), but may not split their movement to do both.

Stacking:

Each surface hex can hold up to four non-flying units and two flying units. Subterranean hexes can hold two non-flying units. Flying units can not operate on the subterranean map. Structures can not be built underground.

Zones of Control:

Non-flying units in Mine-Shaft Gap create a “zone of control” in the six hexes surrounding them. Enemy units must stop their movement upon first entering a zone of control. They may leave the zone of control on a later turn at no movement penalty, but must stop movement again should they enter the zone of control of that or another enemy unit. Units occupying drilling stations or resource hexes can not extract resources if within an enemy zone of control.

Combat:

Combat, like movement, can be conducted by any number of a player’s units, provided each one has a viable target, and provided that no unit attacks more than once in a turn. A viable target is any target within the attacking unit’s range. The range of combat units, expressed in hexes, is the middle number on the bottom edge of a unit’s counter. The lack of a number in this position means the unit can only attack adjacent units. “Line of sight” rules only apply to subterranean combat. That is, as common sense should indicate, underground units can not be targeted by enemy units “around the corner.” Attacking and defending units must be connected by a straight line of tunnel hexes. Line of sight is also blocked, underground, by intervening units.

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Units in stacks need not attack together, but stacked units do defend together. That is, if one unit in a stack is attacked, all units in that stack must be attacked. Any number of units can attack together, provided the target unit or stack of units is a viable target for each attacking unit. Flying units are never considered stacked with any other units, flying or otherwise, for defensive purposes, and can only be attacked by other flying units.

Combat uses a combat-odds system, in which the combined attack strength of all attacking units is compared to the combined defense strength of all units in a defending stack. The strength of units varies, however, depending on their relative elevation. Surface combat carried out by ground units follows the following rules:

The attack strength of each non-flying unit is calculated by multiplying its base attack strength – the number printed in the bottom left corner of its counter – by its elevation. A unit with a base attack strength of three, for instance, attacking from high elevation, has an effective attack strength of twelve. Higher elevation, therefore, is a tactical advantage when attacking ground units. Subterranean combat is assumed to take place at the same level; no multiplying of attack strengths takes place in underground combat.

Flying units, on the other hand, have their base attack strength multiplied by the elevation of their target or target stack. Thus, while high elevation gives you an advantage in attacking other ground units, it leaves you exposed to attack from above. The same rule is true for orbital strikes: the base attack strength of twenty is multiplied by the elevation of the units in the hex under bombardment. Since orbital strikes take place in a separate phase, of course, they cannot be combined with other forms of attack. Ground units and flying units may combine in one attack.

Units defending in mountain hexes have their defense strength doubled. Jump troops defending in crater hexes also have their defense strengths doubled.

Once the total effective attack strength of the attacking force is determined, it is compared to the total defense strength of the target unit or units as a ratio, rounded down in favour of the defender (in typical microgame fashion). A die is rolled by the attacking player and the following combat results table is consulted to determine the fate of the defending units.

Odds Ratio:

Die Roll:

1 - :3 1:2 2:3 1:1 3:2 2:1 3:1 4:1 5 +: 11 CA CA CA NE NE CI/EX CI/EX CI/EX CI/EX2 CA CA NE NE CI/EX CI/EX CI/DD DD DE3 CA NE NE CI/EX CI/EX CI/DD CI/DE DE DE4 NE NE CI/EX CI/EX CI/DD CI/DE DE DE DE5 EX CI/EX CI/EX CI/DD CI/DE DE DE DE DE6 CI/EX CI/EX CI/DD DD DE DE DE DE DE

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Treat CA results as NE, and EX as DE, when resolving orbital bombardment attacks.

Interpreting the Results:

CA: Counter-attack! The defending forces suffer no casualties and mount an immediate counter attack using basic (unmodified) attack strength vs. basic defense strength. Ignore any CA results rolled during the counterattack. This is the ONLY time that flying units can be attacked by ground units. If the attacking units are not all in one stack, the defender may choose which stack or stacks to attack.

NE: No effect.

EX: Exchange. Starting with the defending player, each player alternates eliminating one unit at a time, until one player is out of units. Only units involved in this combat are affected. Flying units may also be lost this way.

CI: (Subterranean combat only) Cave-in! The tunnel is blocked. Place a rubble counter in the hex of the attacking player’s choice between the two forces. If tunnels are being represented by markings upon the hex map, simply erase or draw a line through the tunnel at the specified point. The blocked hex must be drilled through in the usual way to reopen the tunnel.

DD: Defender disrupted. All defending units are damaged. Flip them over; they may not act in any way this turn. They do not exert zones of control while damaged, and any further DD result will destroy them. Flying units are destroyed immediately by a DD result. Damaged units defend at full defense strength. Structures are not affected by this result. Units become undisrupted at the end of the combat phase in the owning player’s next turn, regardless of whether they were disrupted during orbital bombardment or regular combat.

DE: Defender eliminated. All defending units are destroyed.

End Phase

At the end of the turn, each player checks to see if he or she has reached the total number of points necessary to achieve victory. If the first player reaches this total first, the second player still plays out his or her half of the turn. If both players achieve the victory-point goal, victory goes to the player with the highest total basic attack strength in undamaged units on both maps.

If, at any time, one player has no units left on the map, the game ends and the player with the higher victory point total wins.

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Charts and tables:

Counter diagrams: Build Cost:

Drill Tank 8

Missile Tank 8

Hover Tank 7

Utility Vehicle 6

Staff Car 7

Jump Troops 6

A Command Centre Free at start of game

> Tunnel Opening No build cost

2 Drilling Station 5 + elevation level

c Command Post 10, or + 5 to Drilling Station

Strike Jet 12

Assault Jet 13

Movement value and type Indicates mining capability Unit silhouette

Attack strength Range Defense strength

11

6T M

2 2 2

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Turn Order:

Orbital Scanning PhaseBombardment PhaseResource Extraction PhaseResource Allocation PhaseMovement/Tunneling PhaseCombat PhaseEnd Phase

Terrain Types and Movement Costs:

Movement: Terrain Type:Type:

(No symbol)=Clear: U=Rough: 5=Mountains: K=Crater:W 1 2 -- 3T 1 1 3 2H 1 1 -- 1F 1 1 1 1J 1 1 2 1

Elevation:

Low elevation: level 1

Basic elevation: level 2Raised elevation: level 3

High elevation: level 4

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Market Conditions:

Die Roll: Victory Point Cost:1 One metal ore resource point + one fissionable material

resource point2 Two fissionable material resource points3 Two fissionable material resource points + one metal ore

resource point4 Three fissionable material resource points5 Two metal ore resource points + one fissionable material

resource point6 Two metal ore resource points + two fissionable material

resource points

Combat Results Table:

Odds Ratio:

Die Roll:

1 - :3 1:2 2:3 1:1 3:2 2:1 3:1 4:1 5 +: 11 CA CA CA NE NE CI/EX CI/EX CI/EX CI/EX2 CA CA NE NE CI/EX CI/EX CI/DD DD DE3 CA NE NE CI/EX CI/EX CI/DD CI/DE DE DE4 NE NE CI/EX CI/EX CI/DD CI/DE DE DE DE5 EX CI/EX CI/EX CI/DD CI/DE DE DE DE DE6 CI/EX CI/EX CI/DD DD DE DE DE DE DE

Treat CA results as NE, and EX as DE, when resolving orbital bombardment attacks.

Interpreting the Results:

CA: Counter-attack! The defending forces suffer no casualties and mount an immediate counter attack using basic (unmodified) attack strength vs. basic defense strength. Ignore any CA results rolled during the counterattack. This is the ONLY time that flying units can be attacked by ground units. If the attacking units are not all in one stack, the defender may choose which stack or stacks to attack.

NE: No effect.

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EX: Exchange. Starting with the defending player, each player alternates eliminating one unit at a time, until one player is out of units. Only units involved in this combat are affected. Flying units may also be lost this way.

CI: (Subterranean combat only) Cave-in! The tunnel is blocked. Place a rubble counter in the hex of the attacking player’s choice between the two forces. If tunnels are being represented by markings upon the hex map, simply erase or draw a line through the tunnel at the specified point. The blocked hex must be drilled through in the usual way to reopen the tunnel.

DD: Defender disrupted. All defending units are damaged. Flip them over; they may not act in any way this turn. They do not exert zones of control while damaged, and any further DD result will destroy them. Flying units are destroyed immediately by a DD result. Damaged units defend at full defense strength. Structures are not affected by this result. Units become undisrupted at the end of the combat phase in the owning player’s next turn, regardless of whether they were disrupted during orbital bombardment or regular combat.

DE: Defender eliminated. All defending units are destroyed.

Resource Setup:

Die Roll: Resource Symbol Used:1-2 s3-4 S5-6 T

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