there is no way to become a fullbringer the only way is to have the mother infected with hollow reiatsu so the child is born with parts of hollow powers thus becoming a fullbringer need an object to release the fullbringer, but to use the common skills like the lightbringer not

the MC's hatsu is very strong as an MUI with the ability to see the future. Only limiting factor now is the MC's body strength but I think that will be fixed when unlocking the pirate class