What are fantastical elements that will be a part of this world?
- Magic. Magic exists and it works. It's not safe, and it's not reliable, but it functions, if you're both lucky and good.
- Spirits. Ditto.
- The cataclysm. The lie is a lie about something that happened in the past - something terrible, and mysterious, and genuinely supernatural/unnatural.
- The gods??!! I think religion can totally be its own post.