[quote=@Ayazi]
By the way on the rules and mechanics on the OP, "Attacks and Noble Phantasms aren't on the same scale as END." What does END mean? Also is their a rule on gender-bending a servant?
[/quote]

END is the Endurance/Constitution stat. It's the Servant's "HP", basically. That statement means that the strength stat isn't a 1:1 to END, so for instance hitting someone with C rank END when you have C rank strength won't be a one-hit KO.

Genderbending is fine.