The Scorched Earth (The Chaos Born, Book 2) - Drew Karpyshyn

The Children of Fire—four mortals touched by the power of Chaos—each embody one aspect of a fallen and banished immortal champion: Keegan, the wizard; Scythe, the warrior; Cassandra, the prophet; Vaaler, the king. Grown to adulthood, the Children are in search of the ancient Talismans that can stop the return of Daemron the Slayer, ancient enemy of the Old Gods. But in acquiring Daemron’s Ring, they unleashed a flood of Chaos magic on the land—leaving death, destruction, and a vengeful queen in their wake. Now, beset on all sides by both mortal and supernatural enemies, they realize that their strength and faith will be tested as never before. And their greatest trial will be finding Daemron’s Sword, the last of the ancient Talismans, before the entire mortal world is engulfed in the war and Chaos that will herald the return of the Slayer.