Let's just wait for the others because it will help!
Hashirama is the 1st Hokage and a Wood Style user, Tobirama is the creator of Hiraishin and a strong water user. The Senju Clan were extinct since the 4th Great Ninja War and today's modern era, Senju DNA is illegal and mostly smuggled as many form of drugs in the black market,a lot of gangsters and drug addicts take on Senju DNA, Senju DNA is the new Marijuana, Heroine and Ecstasy. Senju DNA is meant for medical surgeries, it is a medicine that is mass reproduced by the DNA of Hashirama as well from corpses of other Senju.
LOLTROLOLO! Daily dose of weed in today's generation.