Megami Kōri: Rise of the Empress of all that is cold

A Meteor the size of a grain of sand was headed towards earth at the speed of light. When it hit 3,000 lives were lost, 5,000,000 gained fire powers. Several smaller explosions scattered across the planet claiming 30,000,000 lives. People lived their lives like nothing happened for a few years. Then they came, beasts of ice looking like normal animals but white and/or blue and extremely deadly, some even used their ice powers. At first those who gained fire powers fought them but were quickly overwhelmed. Then the world slowly started freezing over, one splotch of land remained unfrozen, eventually people started turning into monsters when exposed to the cold for too long. They became beings with no rational thought; their only desire was the end of humanity. Humanity split up, some moved underground, while others moved to the only unfrozen land.