To Mine one of the Crystals from below the Game Board, you must play one or more Mercenary cards that fulfill both these criteria:
• All the cards must be of the same color as the Crystal being mined,
• The sum of the levels of the cards must be equal to, or higher than, the mining cost of the Crystal.
The mining cost of a Crystal is reduced by 1 if you have the Faction Totem in that color. If this reduces the cost to 0, you do not have to play a card to Mine the Crystal, but you must still use an action to do so.
Wild Crystals: In each game, two sets of Mercenary cards will not be used. The Command cards of the colors not in use were placed to the right of the Game Board during setup. Crystals of those colors are known as Wild Crystals. To Mine them, you can use cards of any color, as long as all the cards are of the same color.
Example: Lisa wants to Mine a yellow Crystal with a mining cost of 6. In order to do that, she must play Metanel (yellow) cards with levels that have a total value of at least 6. She could play a level 1, a level 2 and a level 3, for example. If yellow Crystals are Wild (the Metanel mercenaries are not in the game), she can Mine the Crystal using a set of Mercenary cards of any single color, with levels totalling 6 or more.
CAVE-IN: If you Mine a Crystal with a CaveIn symbol on it, move the Cave-In token one step to the right along the Cave-In track.
When you Mine a Crystal, place it face down in front of you. You are free to look at the Crystals you have collected at any time, but they are not obliged to show them to other players.
The Faction symbols that are sometimes found on Crystals grant extra Victory Points at the end of the game.