Raiders that are normally enemies, band together to steal energy of Earth. But they bring with them realities that turn parts of Earth in someplace else.
This is Book One of the Possibility Wars. I would characterize this book as sci-fi/fantasy. The rear cover states: "Later today, early tomorrow, sometime next week...the world began to end. The day turned to night, submerged beneath dark clouds and rumbling thunder. A storm filled the sky bloated with poisonous rain. And the storm had a name...
The raiders came from other cosms, bitter enemies joined together to steal the awesome energy of Earth's possibilities. They brought with them their own realities, turning portions of the Earth into soemplace else. All that stood between the invaders and total victory were the stormers, men and women who weathered the violent reality storms unchanged. A selet few of these became storm knights, carrying the battle back to Earth's deadly foes.
Andrew Jackson Decker, a United States congressman who believes in the American dream. Tolwyn Tancred, a paladin from another cosm sent to aid Earth. Together they and their companions attempt to do what no one, in any reality, has done before-to defeat the raiders and their leader, the Torg!"