In Nasuverse terms, iirc, unless Ramesses II has some sort of gift from Thoth or another Egyptian/Persian god or goddess of wisdom or defense, he can't touch Lycodrake Aptera personally.
Blessed by every god there is.
Edit: By the way, I feel I should make this clear; All Phantasmal Beasts' of Ramesses besides the Sphinx are under Mook laws and can be killed at will
within reason. For example, Law definitely can't kill the Hadhayosh alone, but Magos can still dictate it's actions without my consent to a degree.
If you can look at your character in question and go "This guy can take a Divine Beast, who are equal or stronger than a fair number of Servants and have Magic Resistance that makes Saber's look like garbage", then you're free to do with them as you wish. Do keep in mind that I might still detail part of their actions.
As for the number of them, well, I sorta decided on that he can have around seven out without activating Ramesseum, though he can go two or three above that if he tries hard and has breathing space to concentrate in.
