In reading order
Max Abaddon and the Will: A Max Abaddon Urban Fantasy Novel
Justin Leslie
Max Abaddon and the Purity Law
Justin Leslie
Max Abaddon and the Gate to Everwhere
Justin Leslie
Max Abaddon and the Dark Carnival
Justin Leslie
Max Abaddon and the Crystal King
Justin Leslie
Max Abaddon and the Long Bite
Justin Leslie
Max Abaddon and the Gates to Perdition
Justin Leslie
Max Abaddon and the Path of Blood
Justin Leslie
Max Abaddon and the Rise of the Old Gods
Justin Leslie