Ambiguous Chalice can be obtained by having Semiramis reach Bond Level 10.
Ambiguous Chalice is Semiramis' Max Bond CE and exclusive to her.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
Black Holy Grail (The Black Grail)
Medb
Brynhildr (Brynhild)
Fate Grand Order Farming Items
4th Singularity: London
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon