So you ask for a blod magic spell withoat knowing what is blod magic? That makes perfect sance
Anyway there is no such thing as blod magic, its just random type of magic in which you use your (or sometimes someone else's) blood as any other spell ingredients like insances (or even a apple if its energy is usable for the spell) so forget the idea of blood magic
p.s. How can anyone suggests a spell if you don't ask a porpise, if you just want to do random magic THAN REMEMBER MAGIC IS NAIGHTER A TOY OR FOR AMUSEMENT!!!