It was a makeshift plan for Raze, but when he urgently needed to appear in front of cameras and screens, he needed to think of something to hide his identity fast. He had given away the robe that covered his face, and the effects of the robe, in the first place, were subpar compared to the blazer that he had.
So he had used his Dark Magic to cover his robe, as well as his face. Constantly activating it was a hard task, but Raze didn't worry too much about running out of mana at the time. If he did, then simply his body would have disappeared, and he still had his special Cursed Pill that could have activated.
The answer that Alen had given him in order to beat Time Magic was to activate his Dark Magic first. So this was one way, but he would quickly lose the fight doing so. So the answer was to enchant his current equipment with a type of Dark Magic enchantment.