Gwenael — Barbara Hambly

A novelette of 15,000 words, sequel to Hambly's Sun Wolf and Starhawk novels. Former barbarian mercenary Sun Wolf re-visits the ruined fortress of the Wizard-King, hoping to find the books of magic that the dead sorcerer hoarded. He finds, instead, that a) the defenses and curses that Wizard-King set on his fortress are still very much active and b) there are other mages, as inexperienced as himself, in quest of those books: mages who will stop at nothing to get to them first.