Mutating Worlds

When the 16 gates opened the world was sent into chaos, demons and angels invade earth in their never-ending war, and the humans only chance of survival is the new powers they are gaining due to the mystical energies now surrounding them. Klaus Schnieder is on a trip to England when the gates open and his only hope is the one power he gets, the Mutating System. I use the 9 hells and 7 heavens from D&D as the basis for heaven and hell in this world. I am very atheist and do not know much about religion so please do not shout at me if I get something wrong.