Power Miners is a sub-theme of LEGO.
Power Miners is a theme released by LEGO in January of 2009, and was discontinued in 2010. It is similar to the Rock Raiders theme, and may be considered as that theme's spiritual successor. Short biographies for the crew, as well as the complete assortment of monsters—including the Crystal King—could be found on the Power Miners sub-site during the theme's run. These pages have since been discontinued along with the theme.
Between 2009 and 2010, two generations of the theme were released. The first is the 2009 generation, in which the Power Miners are deep in the crust of the Earth. In this generation, they fight the Rock Monsters, including the deadly Throwing Monsters and the powerful Crystal King. The Miners use plastic molds of dynamite, rather than a 1-by-2 plate with a dynamite printing as seen in Rock Raiders and other preceding sets. The 2010 generation charts that the Power Miners have drilled into the volcanic recesses of the Earth's core. The team faces the Lava Monsters, including Eruptorr, the king of the Lava Monsters. Instead of fighting the Lava Monsters with Dynamite—in 75% of the sets, the miners do not—they use water cannons.