Originally Posted by Prime32
...has techniques which ignore his opponents' defences outright (Zanmaken Nii no Tachi could hit J'onn while he's intangible...
Debatable, to say the least. When the rules of two universes contradict each other, your favourite characters rules do not necessarily take presidence.
Anyway, Negima Wiki
says that the technique "cuts a demonic spirit behind a person without injuring the person." Martians don't count as demonic spirirts.