Like the two installments before it, King’s Quest III was a great commercial and critical success upon its release. Fans were initially confused as to what its protagonist, Gywdion, had anything to do with the adventures of King Graham. After a few months passed, they answered the questions for themselves, and began seeing King’s Quest III as the best game in the series thus far. Whether or not a sequel would be made was never a question, for Roberta Williams and her team dropped many hints throughout their game that King’s Quest IV lurked just around the corner.
Though the visuals had improved in subtle ways since the inception of Sierra’s Adventure Game Interpreter (AGI) engine, it was beginning to show its age. In 1987, LucasArts released Maniac Mansion. This unique take on the adventure game genre ended up being a grand success in its own right, impressing critics with its cast of characters and smart humor. Among those who praised it was acclaimed science-fiction writer Orson Scott Card. In the face of this fierce, new competitor, Sierra needed to step up their game to remain relevant. This led to the creation of the AGI engine’s successor, SCI. Interchangeably referred to as both the Script Code Interpreter and Sierra’s Creative Interpreter, this new engine was designed by programmer Jeff Stephenson
With the outdated engine ready to be replaced, there was no better game Sierra could have chosen to than the latest installment of their flagship King’s Quest series. However, as the engine was designed specifically for 16-bit little-endian computers, they realized longtime fans may not have the specifications required to run a game made with the SCI engine. On top of that, the engine had not yet been proven commercially. Therefore, Ms. Williams and her team opted to develop two versions of the game concurrently: one would be built using the AGI engine and the other upon the SCI engine. The former was intended as a fallback in the event the latter didn’t sell. Fortunately for Sierra, the series’ fourth installment, entitled King’s Quest IV: The Perils of Rosella, ended up moving 100,000 copies within two weeks of its debut in August of 1988. Even better, the SCI version comprised a majority of those sales, eliminating the need for its AGI counterpart, which was discontinued mere months after its release. The commercial success of King’s Quest IV proved beyond any shadow of a doubt the sheer popularity of the series. Was the new SCI engine what the series needed to evolve?