Board Thread:Naruto Discussions/@comment-33485854-20180606215933/@comment-734582-20180608195109

UltimaDude wrote: It's clearly Kurama Sage Mode (Kurama Mode + Sage Mode). Design wise? Yea. Feat-wise, it seems to me like it was simply meant to be SPSM, but they lacked the final designs when they went in production. Naruto was only shown easily interacting with TSB's (e.g. kicking them) in SPSM. I find it more believable he tanked that giant golden sword in SPSM (where he has aforementioned resilience against TSB's ) than KSM. Similarly, it makes no sense that he whips out SPSM at every point since then, even against the comparably weak Shin, yet resorts to an inferior form for a fight against a nigh-god-like entity.

Hence my earlier comment: The Last's mode is supposed to be SPSM, even though it's not drawn that way.