Okay, let's keep on going here. Actually....I'm not really sure what would happen if the One tried to kill Mar.
See... most of Mar's magic works by taking some of his own Mass and then using this as the "more-than-equivalent exchange" fuel required by physics. This is why, since Mar's not quite connected correctly to his Highest self, using any magic that creates anything doesn't work. He'd be in effect asking Entropy to take the payment out of only his Mass, and well......that's a really bad idea. XD
But I'm not really clear on whether the same situation applies to The One at all. Mar's mortal, so if the guy landed a blow on him...well Mar the character's as dead as anyone else. x___x