Clear Skies by H.M. Wolfe

Three months have passed since Ardan appointed Elias as his successor and decided to build a town around The Base. Content with the progress of his apprentice, he even contemplates a semi-retirement when Elias turns twenty. But, as the saying goes, no rest for the wicked.
Memories of the time they spent on the island of horrors come back, haunting the sleep of Tarrin, Ira, Elias, and Abernathy, threatening to destroy the budding relationship the four of them share. Things go from bad to worse when Ames returns, after lying low for more than a year.
It’s time for the leaders of The Base to join together in supporting Elias’s decision to take down Ames himself—an act of justice for the monster’s numerous victims… and personal revenge. But will Elias possess enough strength to see it through to the end, chasing away the black clouds and clearing the skies?