Kon El
Genetically Modified
Incorrect. Cain is only greater than human when he is the Juggernaught which involves manipulating the Ruby of Cyttorak. As I understand it though, his powers were lately revoked by Cyttorak leaving only an increase in his physical strength at a base level, but he has to breath etc so that's wrong for a start.
Secondly, even if we aren't talking about that version, the ruby does not protect Cain's head from penetrating attacks. He could be lobotomized.
Thirdly, The usage of the helmet is to filter strong light and protect his head. Not ONLY from telepathy but also from attack. That is WHY the helmet is there. In many versions his helmet is removed and he's using a different version that can not only not block telepathy but also can't block super-strong physical attacks. The head was always designed as the only possible weak point in his body.
Forthly, the constraint of his power is to foes not native to this planet. a la Glads, a la phoenix, and I'm guessing a la DD. He would be STOMPED. He has no way or means of defeating DD and I notice that everyone is hopping on the bandwagon of how DD couldn't defeat him, I have given many ways in which he could in fact defeat him - but conversely how could Juggernaught defeat DD? answer - he couldn't.