|Title:|| The Seven Rings that Cover the Fiery Heavens|
7 Rings of Heaven (English localization of Extra)
|Transliteration:||Shitenoou Nanatsu no Enkan|
Rho Aias: The Seven Rings that Cover the Fiery Heavens (熾天覆う七つの円環, ?) is the shield used by Aias, and the only shield capable of stopping the javelin of the great hero Hector. It was a bronze shield covered in seven layers of oxhide, which the javelin, having never before been blocked during the Trojan War, pierced to the seventh layer before stopping. Its existence was sublimed into a Conceptual Weapon that is said to be an absolute defense against any thrown weapon. It takes the form of seven layered Bounded Field in the shape of an iridescent flower in reference to the rocket larkspur (Consolida ajacis) flower that bloomed from Aias' blood as he died, with seven petals representing the seven layers of oxhide. Each layer has the defensive power of a fortress wall, and Archer cannot personally recall any thrown lance that would be capable of penetrating even the first layer. It is necessary for its user to provide constant magical energy to form the shield, and if it is damaged, they will feel pain and receive damage in accordance.Archer came into contact with it some point in his life, and added it to his library of weapons and defensive armaments stored in Unlimited Blade Works. He uses it as his main defense, as it is the one in which he has the most proficiency, and Shirou Emiya cites it as Archer's greatest protection. He uses it to defend against Lancer's Gáe Bolg, which manages to pierce up to the seventh layer before finally stopping. This action takes much of his energy, as it takes three times the amount of prana as a weapon in order to project it, and Gilgamesh's Enuma Elish without either of them realizing it. If it is used by Shirou after having access to Archer's knowledge, he is only capable of generating four petals in Heaven's Feel and Fate/hollow ataraxia. It is still powerful enough to help Bellerophon overpower Black Excalibur and temporarily deflect a charged shot of Hrunting. Shirou is able to project the full version during Unlimited Blade Works after "pulling it from the hill" of the Reality Marble in order to protect himself from Gilgamesh's onslaught of swords.
Fate/complete material III: World material - FAQ with Nasu: General Questions about Fate, p.130-131
Q: In the end of the Rin route, was it Shirou that projected Rho Aias in the Shirou vs Gilgamesh fight?
Q: In the end of the Rin route, was it Shirou that projected Rho Aias in the Shirou vs Gilgamesh fight? Or was it Archer? In Fate/side material, it's said that it was projection magic from Archer, but in the story, there was the depiction of Shirou "pulling the shield from the hill". Does this mean that this switched to Archer's scene?
A: This has been easy to misunderstand, but the part about Archer supporting Shirou was the time before Shirou pulled out Rho Aias, before Shirou came to his realization. After Shirou's monologue about his surprise that he was still alive after taking Gil's attack, "If I survived, there must have been a reason why I survived. But that was simply something I didn't have any control over." That was the "Rho Aias" that Archer made to help Shirou in a way that wouldn't let Gilgamesh know there was someone else waiting to ambush him.
 Fate/side material - Encyclopedia: Rho Aias [Noble Phantasm], p.078-079 English | Japanese
Rho Aias [Noble Phantasm]
The Seven Rings that Cover the Fiery Heavens