Lord of Secrets by Breanna Teintze From Goodreads: Magic is poison. Secrets are power. Death is . . . complicated. Outlaw wizard Corcoran Gray has enough problems. He’s friendless, penniless and on the run from the tyrannical Mages’ Guild – and with the search for his imprisoned grandfather looking hopeless, his situation can’t get much worse. So when a fugitive drops into his lap – literally – and gets them both arrested, it’s the last straw – until Gray realises that runaway slave Brix could be the key to his grandfather’s release. All he has to do is break out of prison, break into an ancient underground temple and avoid killing himself…