|Title:||Self Seal, Dark Temple|
|Transliteration:||Jiko Fuuin Ankoku Shinden|
|Maximum number of targets:||1 person|
Breaker Gorgon: Self Seal, Dark Temple (自己封印・暗黒神殿, ?) is a bounded field used by Rider mainly as a Mystic Eyes killer to suppress her powerful Mystic Eyes of Petrification. It is a powerful bounded field the same size as the temple of blood that "covered the world" of the Shapeless Isle inhabited by the Gorgon Medusa, but the "Temple of Darkness" differs from it by "sealing the world" instead. Differing from Mystic Eyes, it will affect others as long it is steadily provided with user's prana and the target is within range. Within the limits of the bounded field, all abilities that affect the external environment will be suppressed and all individuals will have their consciousness entrapped into the Gorgon's mind. Furthermore, those entrapped will see nightmares of mixed delight and taboo. Perseus used Kibisis to reverse the effects, forcing the Gorgon Medusa to see all of the nightmares in her heart. It showed her a dream where she was harassed by Stheno and Euryale, but she felt it wasn't so bad to be able to see the sisters that she could not longer meet even if it was a nightmare.
Rider applies the bounded field to her own self in the form of a eye cover to keep her Mystic Eyes from affecting those around her by using its ability to "seal all magical properties". It also completely seals her sight, so she instead perceives the world through senses such as hearing, touch, smell, and magic-detection to acquire more precise information than sight. She replaces it with a Mystic Eyes killing pair of glasses at the end of the Heaven's Feel route and Fate/hollow ataraxia. They do not act on all magical properties like Breaker Gorgon, so only seal the effects of her Mystic Eyes. Once she releases it, her eyes can be used continuously to affect her enemies. Upon entrapping a target within the bounded field, it can be used to hold the target in place and prevent them from attacking. She can also use the illusions to disguise her deeds of collecting energy from them in the form of wet dreams. She uses it on Shirou Emiya during Heaven's Feel to collect energy for Sakura Matou. She shows him a sexual encounter with Rin Tohsaka in the original Fate/stay night to collect his semen, and she shows a suggestive scene between Rin and Ayako Mitsuzuri in the Realta Nua version to collect his blood.
Fate/complete material III: World material - FAQ with Nasu: Noble Phantasms, p.134
Q: Rider's eye cover, Breaker Gorgon, does it allow her to see what's before her?
Q: Rider's eye cover, Breaker Gorgon, does it allow her to see what's before her? Also, the Mystic Eyes Killer Rider is wearing, does it have a comparable sealing power as this Noble Phantasm?
A: Her sight is completely sealed. Although Rider perceives the world through senses such as hearing, touch, smell, and magic-detection, she is able to acquire more precise information than sight.
About the glasses, it only seals the power of petrification. It does not act like the Breaker Gorgon, which "seals all magical properties".
 Fate/side material - Encyclopedia: Self Seal - Temple of Darkness [Noble Phantasm], p.062 English | Japanese
Self Seal - Temple of Darkness [Noble Phantasm]
A Mystic Eye Killer applied to oneself.
It was the blindfold of Rider's, which sealed the excessively powerful Mystic Eyes into a boundary field (another World).
Shirou's erotic dream in Sakura route was a result of being drawn into this Temple of Darkness. In this World, Shirou had an erotic encounter with Rider in disguise, and had some of his blood and semen drained.
Anyways, the blindfold had meaningful purposes.
"Hmmm, was the blindfold just for style and fun points?"