Overview

Cavum is an abstract tile-laying strategy game by Wolfgang Kramer where players are miners digging tunnels through a mountain, establishing mining stations, mining precious gems, and selling them to fulfill contracts or on the open market. The game is played over three phases, with each player getting 12 actions per phase. Players build tunnel networks connecting stations to gem veins, compete for contracts, sell loose gems at market prices, and establish presence in surrounding cities. The player with the most points after three phases wins.

Components

• Game board with hexagonal grid (mountain area with 5 surrounding cities)
• Tunnel tiles (hexes with various numbers of track exits)
• Gem vein tiles
• Dynamite tiles
• Mining station tokens (per player)
• Gems in 6 colors (including 9 yellow gems for the central vein)
• Market price tracks (numbered 1-9 per gem color)
• Contract cards
• Joker tokens
• Turn order chips (1-4)
• Victory point tracker

Setup

1. Place the game board centrally. The mountain is a hex grid with 5 cities along the edges (varying in size from 5-7 hexes).
2. Place 4 X tiles in the start city (5-hex city).
3. Place 9 yellow gems stacked on the central hex (the initial yellow gem vein).
4. Set up market tracks for each of the 6 gem colors: place one gem on each space numbered 1-9. The market value of a gem equals the lowest visible number on its track.
5. Shuffle contract cards and prepare them in a draw pile.
6. Each player receives their set of tunnel tiles, station tokens, and starting resources.
7. Determine starting turn order.

Turn Structure

The game is played over 3 phases. Each phase follows this structure:

1. Contract Display: Add 5 new contract cards to the display. Each shows required gem combinations, point values for completion, and penalties for non-fulfillment.
2. Turn Order Auction: Players bid victory points for turn order chips (1-4). Lower numbers act first.
3. Action Rounds: Players take turns spending 1-4 actions per turn from their pool of 12 actions. When a player’s actions are exhausted, they pass for the rest of the phase.
4. Phase End: Resolve dynamite explosions. Conduct gem sales (contracts and loose gems). Score city presence. Prepare for next phase.

Actions

Place a Tunnel Tile (1 action): Place a hex tile with tunnel exits on an empty mountain hex. Tiles can be stacked on top of existing tiles if the upper tile has more exits than the tile beneath.

Place a Gem Vein (1 action): Place a vein tile on the board. Each vein contains 4 gems initially. Veins can be placed atop other tiles.

Place a Dynamite Tile (mandatory, 1 action): Each player must place their dynamite tile once per phase. At phase end, dynamite destroys all adjacent tiles (not veins or tiles with stations). This is both offensive and defensive.

Establish a Mining Station (1 action): Place a station token on a tile in the mountain or in a city hex. Stations anchor your tunnel network and protect tiles from dynamite.

Use Joker Token: Swap a joker for an item from the common pool, or discard it for 3 victory points.

Prospecting (mandatory final action): Your last action each phase must be the prospecting action. Trace an uninterrupted, unrepeated path from one of your stations to another, collecting gems from any veins along the path. Gems collected go to your personal supply for selling.

Scoring / Victory Conditions

Three Scoring Methods:

1. Contract Fulfillment: Turn in the required gem combinations shown on contract cards to earn the listed victory points. Contracts taken but not fulfilled incur a penalty (lose some VPs). Contracts average a gem value of 7-8 points per gem, making them generally the most profitable way to sell.

2. Loose Gem Sales: At the end of each phase, for each gem color, players bid the lowest price they’re willing to sell at. The market value of a gem equals the lowest visible number on its track. When a gem is sold (via contract or loose sale), it is returned to the market track, reducing the price. Players compete to sell at favorable prices before the market drops.

3. City Presence: If you have an active station in a city (connected to another of your stations in the mountain), you score points equal to the number of empty hexes in that city. Stations must remain connected to be active.

Game End: After three phases, all remaining loose gems must be sold. The player with the highest total victory points wins.

Special Rules & Edge Cases

• Tunnel tiles can be stacked if the upper tile has strictly more exits than the tile below.
• Dynamite tiles explode at the end of each phase, destroying adjacent tiles (except veins and tiles with stations). Plan accordingly.
• Gem veins start with 4 gems; once all gems are taken, the underlying tile is revealed.
• The prospecting path must be uninterrupted and unrepeated; you cannot visit the same tile twice.
• Turn order is crucial since gem veins deplete quickly; earlier players get first pick.
• City presence scoring requires an active connection from the city station back to the mountain.
• Each phase has exactly 12 actions per player; spend them wisely.

Player Reference

Action	Cost	Description
Place Tunnel	1 action	Lay a hex tile with tunnel exits
Place Vein	1 action	Place a gem vein (4 gems)
Place Dynamite	1 action (mandatory)	Destroys adjacent tiles at phase end
Establish Station	1 action	Place station in mountain or city
Use Joker	1 action	Swap for item or discard for 3 VP
Prospecting	1 action (mandatory last)	Trace path between stations, collect gems

Market: Gem prices = lowest visible number on track (1-9). Selling gems returns them to track, lowering prices.

Scoring: Contracts + Loose Gem Sales + City Presence = Total VP. Highest VP wins.