DOA4's Shippu-Rendan. The real wind dash. Came out as 236f~66. Allowed you a chance to dash through wake up kicks and such. It was dropped in DOA5 as a way to "tone down the ninja's" when while his way was crucial to his game play sometimes, it was the unsafest way out of all 3 ninjas because it didn't instantly put you in the air like with Sumi, Ayane, and Ryu.
The animation too a few frames to get to the i frames and dash meaning you could possibly get clipped by the wake up kick easily while with the other 3, the timing is very flexible. Smh.