Eventide is the second book of the Shadowmoor Cycle. It was written by Scott McGough and Cory Herndon. It was published on June 3, 2008.
Blurb:
The Great Aurora has come ...
No sun will rise over the world of Shadowmoor, and all but a precious few have forgotten the daylit world that once was.
In the perpetual night of Shadowmoor, a few brave heroes will fight the world itself for a last glimmer of light.
... and darkness has won