It definitely is part of what makes Onoki *. I tried using him but it was legit one of the worst experiences ever. Not having any additional effect on his barrier and chase already puts him lower than other ninjas of the same treasure. Even if he buffs tri-element the pro doesn't outweigh the cons.

Backaches do seem to occur way too often. I never hit more than half of my standards with Onoki. Even if you throw out all that theoretical math there is no way you can warrant a ninja hitting less than even 2/3 of his standards a "low chance" failure. Then to top it off his interrupt is on the standard, rather than the chase. Losing standards to his backache *s cause its lots dps and combo potential but as far as control it basically makes no difference. So few ninjas without prompt skills are front line to be interrupted. So even if the standard does go it won't really do a ton. On the flip side if you put it on his chase then at least he can be a reliable interrupt for one or two rounds if your first slots can set it up. The last straw is just the fact that the double standard passive, although noted as random, can be applied to clones, even ones that don't have an attack. That as a whole is just rather idiotic too and one major downside to all earth ninjas with the passive. Tacking it onto Onoki though just makes him a failure of a ninja all the way around honestly. His mystery stopping revives hardly makes up for all the * tier components he has going otherwise.