User blog comment:Clovis77th/Similarity between Jack the Ripper's mystery and the Hassan/@comment-49.146.192.146-20170422000701/@comment-29543192-20170427212314

Well, this had nothing to do with power.

For FGO power levels, they have to balance the strength among other classes making them strong in-game and not in-universe. For star rank, more famous servants will be higher, like how Jack is 5 star, while most Hassans are 3 stars or below, even though they are the original assassins. King Hassan is 5 star because he is awesome and also, the Yorokobe sells. lol