An interesting chapter and I rather suspect that neither Albus nor Narcissa are going to find matters anywhere near as easy as they expect, particularly since they don't realize, yet, just how intensely Harry's new guardians are fighters in their own right; that's going to put quite a kink in a lot of plans. It will be rather interesting to see just where Xander's magic comes from (be amusing if he turns out to be from an old offshoot branch of the Black family, that'd make his position just so appropriate and that much more unassailable).