@Zonko
That's actually not a shark, it's Lancer's icthyosaurus from chapter 104 - you see her absorbing the other servants' power on the panel prior. She's also riding Archer's tornado (which I don't think we've ever seen the archer use).
Lancer is presumably Mary Anning, an early paleontologist who discovered skeletons of numerous prehistoric marine animals (often depicted with that iconic outfit +dog) and Archer is presumably Pecos Bill, the fictional cowboy who was raised by coyotes and rode tornados (often treated as the western folklore/fakelore counterpart to the northern Paul Bunyan).
Assassin is J Edgar Hoover and Rider is Georges Melies. Caster(s) are supposedly based on some Japanese folktale about mice and riceballs? I have no clue who Saber is.