Miners look for places where their desired crystals/gems are abundant and they are here. The card's info says: RB08-EN059: Miner's Sanctuary Field Spell Once per turn: You can activate 1 of these effects based on the number of "My Crystallized Pony" monsters you control: - 1: Inflict 500 damage to your opponent. - 2: Your opponent discards 1 random card. -3: Target 1 monster your opponent controls; destroy that target. - 4: Draw 1 card. - 5: Discard 1 card. Send all monsters your opponent controls to the Graveyard. You cannot conduct your Battle Phase this turn. - 6+: Destroy all Spell/Trap Cards your opponent controls. Rare
