The Tides of Kregen - Dray Prescot, #12

Of all the honours that Dray Prescot, Earthman, has won during his fabulous adventures on Kregen, none are valued by him more than his membership in the Order of the Krozairs of Zy. The Krozairs are the highest order of chivalry on that turbulent planet, dedicated men, warriors of stern convictions and unflinching hearts. Thus, when the Krozairs in their hour of need called on all their far-flung members for aid, he should have gone.
But he could not. His return from Earth was blocked by the anger of the mysterious Star Lords. And before Dray Prescot can achieve redemption, he has two armies opposed to him, two warring kingdoms naming him outlaw, and only the tides of the seven moons as a weapon... The Tides of Kregen is the twelfth book in the epic fifty-two book saga of Dray Prescot of Earth and of Kregen by Kenneth Bulmer, writing as Alan Burt Akers.
The series continues with Renegade of Kregen.