Lionhead has told Eurogamer that work on Fable III is rocketing along at 10-times the pace of Fable II.
In an interview published today, art director John McCormack said having a working engine - albeit one Lionhead wasn't "entirely happy" with by Fable II launch - enabled the team to focus on polish and squeezing the technology that "little bit further".
"[Fable III is] definitely bigger than Fable II by a long way," said McCormack, "but it's bigger in breadth as well. We've got a lot more variation in this one.
"We never had an engine before. Now, with the engine, iteration is faster. We're working at 10-times the speed we ever did on Fable II.
"The framework was there," he added, "and it's the polish now. For us, it's as if they'd started switching things on in Fable III. They'd go, 'Click, there's your specular!' And we'd go, 'Oh look, everything's shiny!' 'Click, there's your normal maps... Ohh!'"
"Working in the dark" with the built-from-scratch Fable II engine, McCormack revealed, was "really scary".
"We'd build things without knowing how it all hangs together - then suddenly the lights are all switched on and you just pray it's not horrible! You'd think, please be like what it was in my head, oh please," he said.
In comparison, then, Fable III development has been relatively "relaxed", thanks to a strong theme and ready-trained team. "We were all raring to go," recalled McCormack.
"That doesn't stop the fact that it was an RPG being developed in, essentially, two years.
Fable III will be released for Xbox 360 on 26th October. A PC version will follow. We played the latest Fable III build this week.