Crystal Guardian

The evil Master of Brimstone, trapped within icy crystal for two years, has finally broken free with the help of his faithful Magician, Dima. He rebuilds his world and begins devising a new method to conquer the Keepers' world and kill Singer Mariachi, who imprisoned him.
Meanwhile, a collapse at the Deep Mines in SpiritShine Valley has forced Gatemaster Sharptooth and the Miners of Redrock Keep to search for new mines. More red slate and diamonds must be found so that the Keepers can continue to build their guardian pillars, which protect both their world and the world of Arkady against Brimstone's attacks.
The Miners must put their search to the side however, when North Slope Mountain in Arkady awakens from its centuries-long slumber and reveals itself to be an active volcano. The imminent eruption forces the Keepers to put all other work to the side as they rush to evacuate the towns within the volcano's reach.