Time, it was the ultimate weapon of the timeless. Having been given one more day by the strange Mayfly that controlled this time-loop, Scar did not waste it. He had spent the entire day today carving these runes in preparation of this battle.
The process of carving was much easier with his latest evolution. Previously he was able to simply create the runes in the air, by pouring spiritual energy through his threads. He still could do that. Now that he could make his threads physical, he could combine it with the new ability to turn his spiritual energy into a burning force that could carve through physical and meta-physical alike.
The result was his threads being turned into runic brands. All he had to do was form the runes with his threads, control the energy and simply press the brand into the surface for quick writing. It was naturally easier said than done.
