I like the idea of turning [-] into [+], as we have a lot of models with hard to wound, stubborn, and other build-in [-] to attack and damage flips against them. So Shinobi finaly have a chance to say "Surprise!" to Yin, Yasunori, Zoraida and many others (: Also their nice ability to push 5" at end of turn after suffering damage from poison will be useful for Take prisoner or Hold up their forces.