Basically his mystery does not cause knockdown.

Do note that the ninjas available and skills available here is much different compared to what CN has right now. Also Tobi got some new skill upgrades in the CN version which increases his dodge and gives him chakra at the start of every turn. Just let this version run through the same course as the CN one.

It will happen around the same time CN version decided to nerf it (no idea when that is) we are missing tons of ninjas and balance changes so just be patient for more content to be released.