This craft essence is currently unavailable on the EN ver.Seaside Luxury is can be purchased from Dead Heat Summer Race! event shop.
Here is a list of servants & CEs that can be obtained for the duration of the Summer 2017 event part 1: Dead Heat Summer Race and part 2: Death Jail Summer Escape.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
Robin Hood
Merlin
Piece of Year 2030 (A Fragment of 2030)
Shining Gem of Bows
Holy Night Sign
Jeanne d’Arc (Alter)
Okita Souji
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon
Black Holy Grail (The Black Grail)