All of Astolfo's noble phantasms are borrowed in some way; the hyppogryph was taken from Bradamante, the book & horn from Logistilla, the lance from Argalia. The only thing that is truly "Astolfo's" is their sword, which they gave away almost immediately to Sieg. And that is very fitting, because Astolfo's strenght doesn't lie in being personally powerful (they're rather ewak by herioc spirit standards) HOWEVER it lies in loving, and being loved. They are loved, and that's why they were gifted so many things. They love, and that's why they have such a huge impact on the people around them.