- The Mu Phase of anyone of Mulian heritage, which their blood turns blue and results in memory loss.
- Made worse by the fact that almost everyone is a Mulian due to that they're related to each other by blood or adoption, meaning that many of them ended up going the Mu Phase.
- Tokyo Jupiter, the barrier surrounding the town, and how it's formed. It has the ability to to slow down time inside of it to one-fifth compared to the outside time.
- Ayato killing a dolem, only to find out that Asahina was linked to it and how she dies and its results.
Nightmare Fuel / RahXephon
RahXephon is, simply put it as, Neon Genesis Evangelion but with the dysfunction, despair, and Kaballah and Judeo-Christian allusions replaced with transcendence and revelation, with musical imagery and Mayan lore added to the mix, and inspiration from Raideen and science fiction literature such as The Dandelion Girl, to produce a result that is thematically the total opposite to the bleakness of Evangelion's climax. Despite those, the series is not without its terrifying moments.