You may ask... "Why ice? I thought his powers is speed" Well actually my explanation is, there is an unknown component in the Speed Elixir that is very cold (colder than liquid nitrogen), and the purpose of that component is to keep Ellis (or anyone he's carrying) from burning up while withstanding the extreme G-forces that can burst a normal into flames (it's some sort of "Temperature Control"). So it means in this stage, that unknown component gets unstable and Ellis's temperature would go down drastically, his mark extends from his left eye, around the back of his head to his right eye then down to his right hand, and then the other end would go down to his left foot and he will be able to create and manipulate black ice. We will have the ability to fly (he creates wings out of ice crystals), more than that he can go faster than 3500Mph. But there are still dangers when he hits the final stage even though he is still in control. Lastly, this is only activated through correct voice prompt (like how Alucard releases his restriction systems).