The punch struck Zein right where his flesh and machine parts connected, resulting in a very unpleasant shattering sound... something inside probably broke. However, the villain had proved time and time again that he could take quite a beating, and it was ever-so-rare for him to be instantly disassembled. This was no exception.
The force from the hit managed to knock the avian backwards, sending a surge of pain throughout Zein's ribcage and causing him to slightly cringe; he hated when that happened. Under normal circumstances he couldn't feel pain, but that was not the case when the organic parts of his body was harmed. That was impressive-- being the majority cybernetic along with his species' size, the avian was fairly heavy and hard to move compared to a human.
...Or was this even human? After the raptor's vision came back into view, he noticed that Mark's hand looked reptilian, almost like a dragon. And, of course, this made Zein very curious to see what was under that power armor. Momentarily changing his tactics, a new idea began to form inside his head: he wanted to get this person grounded, where he could more easily find a way to pick apart his foe. And, from the looks of it, Mark's wings along with the newly reveled hand were his only vulnerable parts, since they lacked a covering.
Finally putting his flight maneuverability to good use, Zein quickly whirled around and attempted to slash with his still-active sword at the base of one of Mark's wings, though it was a rather awkward try since his abdomen was still in pain. He was trying to force him onto the mainland floor, and since he was just beginning to realize just how capable his enemy was, the malevolent raptor didn't hold anything back.