Bill and Ted's Excellent RPG

[vicky_molokh]

Originally Posted by Flyndaran

And completely immutable predestination, something unusual for time travel stories.

Yeah, the Stable Time Loop variant of temporal physics is probably one of the hardest to GM, since it requires envisioning a self-consistent timeline up to and including any last time-travel-into-the-present act from the future, at a moment when one starts a campaign. Works for books and films (Methods of Rationality, Terminator 1 and arguably some of the others, The Girl From Tomorrow as of season 2 etc.), not so much for truly interactive stuff like non-railroad RPGs.