Summer's Rain can be obtained by having Asagami Fujino reach Bond Level 10.
Summer's Rain is Asagami Fujino' Max Bond CE and exclusive to her.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
FGO Reroll Tier List [5/11 updated!]
Best Craft Essence: Craft Essence Tier List
Hero's Proof (Proof of Hero)
Caster
EMIYA
Archer Monument
Elizabeth Bathory (Caster, Halloween)
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon
Black Holy Grail (The Black Grail)