Gatecrash (The Secretist Book 2)

Jace, confronted with the mystery of the Implicit Maze, and the rumblings of a guild war tried to retreat from the action, only to be pulled back in when his friend Emmara Tandris is kidnapped by members of the Cult of Rakdos, thrill kill guild looking to curry favor when more powerful guildmasters.

Jace succeeds in finding Emmara, but the two are now deep into enemy territory, with few options to free themselves.  As Jace struggles to get them to safety, he begins to piece together the greater mystery of the Implicit Maze.  It's now a race to see who will unlock its secrets.