Another minute went by with Grey not stopping his assault. He naturally has a reason for this. Although he wanted to kill Quinn, he knew it wouldn't be easy.
Had Quinn not found out he was following behind him, then maybe he would have done a sneak attack that would end his life or at the very least, injure him, instead of toying with him. But alas, Quinn was too vigilant, and quickly figured out he was being followed.
After being found out, Grey decided it was best to wear him down while also toying with him. This wouldn't only break him physically, but also mentally. Once he's worn down, then the real battle would commence.
But there was one thing he had to make sure of, and that was, as long as he showed himself, then he had to kill Quinn at all cost since he had used two other elements. Quinn would be able to figure out he had five elements that would put his life at risk if the information of him wielding more than three elements were to be disseminated.