Board Thread:Theories and Speculation/@comment-25093611-20160821131910/@comment-27924662-20160823120834

Thekillman wrote: It's not really a speculation since the Jin No Sho calls Shikkotsu forest one of the three unexplored sage regions.

As to "soft vs hard" i don't really see a point there. Orochimaru and kabuto extensively experimented upon themselves for their benefit. I meant about the unique power associated with slug's SM :-|. Slugs themselves providing with SM isn't a speculation...