Quoted from Shapeshifter:Rumors now saying JT was on the Beatles.
On the JT interview on This Flippin' Podcast around the time of GB release, he made reference to the next game that he was working on with ZY being (paraphrasing) "something a little darker and grittier than what he's used to" - that doesn't exactly sound like The Beatles.
(not necessary to link Helter Skelter or Side 4 of The White Album)