Gary had partly transformed his body. His forearms had partial fur sticking out of them, his teeth had elongated, and he had given up on wearing his shoes, transforming his feet and digging them into the ground as he continued to rush forward.
While running at this speed, whoever got in his way was easy for Gary to handle. He could see that there were other roadblocks up ahead that had been prepared, and instead of going forward or using his energy in a fight, he had just jumped off the highway and landed on one of the roads below.
He continued to run down, and then leapt across, reaching another road and digging his claws in, pulling himself up. They were small detours, but it hardly slowed him down with the way he was progressing.
If anything, the thought of those that were still fighting, and those that left him behind, had spurred him on, and eventually he had passed the sign welcoming him into the city.