New gameplay was shown behind-closed-doors at Tokyo Games Show 2015, and now a video of that has appeared online. Check it out above. What strikes me about Ni-Oh is the pace of the game, which is much slower than Team Ninja's titles generally are. Combat looks to be based more around methodical, strategic attacks, as opposed to twitch-based combos.
Interestingly, the main character has multiple stances, indicating there will be a skill-based component to defence. This is different from Dark Souls, in which simply holding a shield up gets the job done.