"Might not be a bad idea to go after him and let him know about it," Sony said, stepping out of the entrance of the Beast's City. "Might as well get to meet his greatest foe."
Sony could trail Denzel's location at any point in time, to be more precise, he could use the scent of his spider webs, tailing it to Denzel's present whereabouts.
Sony could do that normally since he had used his spider webs on him, but it had been long since he did so the whiff might have begun to fade away. That would impel him to use more time than he normally was meant to, and he might end up not locating Denzel.
But with the lasso he made for him, he could always get Denzel's location. He could tell that it wasn't so long Denzel went past that area since he the smell around there was still sharp.