Author give mc Small sword of nth metal. because magical threat can overwhelmed the mc. DC magic is still superior to natural force of chakra also it's not magic.
Hope the mc creates his own team/organization I have found a few members all trained in the art of ninjutsu. He can recruit members like;
1. Red X
2. Cassandra Cain
3. Timothy Drake (before Batman reception)
4. Katana
5. Shado
6. Nightstorm (Prime Earth)
7. Stone (Prime Earth)
8. Cheshire ??