It was a hard slog in 1992 and 1993 thinking through the one complement of R, N, and F, breaking new ground, and then stooping to legalese to protect the idea in patenting. What made more sense, considering what Scrabble(tm) and Monopoly(tm) had done before? There is frankly no other complement strictly speaking mathematically. The template for Rook, Knight, and Bishop, the tie that binds. Many, many candidate offshoots were rejected, some out of hand, some with difficulty. These were pre-Internet days. I don't think I heard the word ''Internet'' until a year later, but obviously technicians had shop talk discussion about it already then. We had respect not to burden others with failed attempts, the dwarfs and giants, the grotesque and abysmal, the puerile and the damned, every insignificant finding. They were cast aside. All those rejects, some half-imagined, become today 90% of the subject matter of Chess Variant Page and such affiliates as Zillions (the latter motivated by filthy lucre -- as we all need to be to some extent). 
With proliferation, any inchoate idea, even regardless of prior art, becomes actualized on screen. They put up ''new CVs'' and leave for historians, one of my specialties, to know whether it is done before. Prolificists rarely have done their homework, as to where their new combination, usually but not always unimaginative, fits into the panoply. The piles of gems amid the rubbish tower high. For example, there are hundreds and hundreds and hundreds of chess and games patents of UK, France, Canada, USA, Singapore, not only a few, of which prolificist CVers are ignorant in their make-believe universe.