Leaves of Flame — Joshua Palmatier

One hundred years have passed since Colin brokered a peace agreement between the human, dwarren, and Alvritshai races. Since then, he has sought ways to defeat the dark spirits called the sukrael and the Wraiths. Colin has gifted each race with a magical Tree to protect them, and stabilized the Wells. But now the enemy has found the one Well that controls the entire network, and if Colin can't find the Well and stop the Wraiths from activating it, it could mean the end of all three races. . . .