A writer doing detailed summaries of Norman's books on a Gor website prefaced his RAIDERS OF GOR synopsis with an astute quote. Up until RAIDERS the writer (nicknamed Socrates) pointed out:
"The stage appears to be set for many adventures in which Tarl, aided, abetted and occasionally hindered by Elizabeth, will foil the plots of the Others in city after city of Gor, while Tarl enjoys James Bond-like romantic encounters over and above Elizabeth's considerable charms and sees many a deserving and brave slave girl restored to freedom, escapes from hair-raising dangers and finds himself unexpectedly assisted by people much better clued-in than he about what is going on. He will surely make occasional progress towards the eventual discovery of his lost Talena, despite his many worries as to the fate of a defenseless woman on Gor."
That is a keen insight down the path the series could have gone, one many readers wish Norman had taken. I, too, would've loved another two or three books with Cabot still in good guy mode like he is in NOMADS or ASSASSIN before Norman veered onto 'the road less traveled by.' But Professor Lange trekked into darker territory and murky emotional waters where Tarl Cabot undergoes a massive paradigm shift, reversing his former notions on the enslavement of women; gone is the squeaky clean firm-jawed boy wonder Cabot and in his place is a more believable and flawed character. RAIDERS is the springboard for the humble beginnings of Bosk of Port Kar, a shattered man in serious denial about many things, one of them claiming not to serve Priest Kings anymore while clearly doing so.
Norman sprinkled clues pertaining to future plot developments large and small early on in the series making obvious the fact he had a long range vision of Gor. He might not have had it when he penned TARNSMAN, but he certainly did once OUTLAW was finished. Cabot first hears of the Others (a major plotline many years and books down the road) in the fourth book, he gets a glimpse of a Kur in the fifth, but never meets one face to face till the ninth book, when the Others nomenclature is all but dropped from the series in favor of Kurii. All those Centurions, Vikings and American Indians traipsing about Gor make perfect sense in Norman's cosmic scheme of things too. The invasion of Ar by Cos and Tyros was also only an inevitable matter of time. On a smaller scale, Chenbar the Sea Sleen and Ivar Forkbeard (among others) are mentioned in conversation in books prior to their actual walking/talking debut on the page.
What makes RAIDERS OF GOR one of the most important books in the series is Cabot's character about-face in chapter three. RAIDERS is not as strong a work as the two previous titles NOMADS and ASSASSINS, but it is an absorbing read and an unpredictable change seeing the invincible dunderhead Cabot with the sandal on his other foot. Forthwith Cabot eschews his dunderheadedness after hundreds of thousands of previous words of prose and wakes up to smell the hot black wine.
It must take some authorial courage to skewer and reinvent a hero on the Tarzanic level of Tarl Cabot and transform him into a fairly unlikable chap. Cabot suffers mental duress in RAIDERS that will greatly impact all the Gor books to come, where both protagonist and planet get meaner and grittier. The next book CAPTIVE takes another huge leap in outlook at the less kind and gentle doings on Counter-Earth.
Then HUNTERS, MARAUDERS and TRIBESMEN rear their awesome heads with the DAW brand and rival PRIEST KINGS, NOMADS and ASSASSIN in quality, storytelling and plot resolution. After those only a few Tarl Cabot novels could even stand in their shadow: BEASTS, BLOOD BROTHERS, PLAYERS and, maybe, REBELS.