Terror kept Merton from realizing what was happening at first, not even color seeping back into the world was enough to calm him. He just continued to cower like he expected Josh to lash out again at any minute, even as static tears starting streaming through the cables and onto the floor. It's not until those cables start getting ripped out and Josh reaches out to them for help, that Merton seems to regain some sense and realize that Hiccup was right. It had worked.

Scrambling over to Josh, he's no less panicked but at least determined to try and help Hiccup tear as many of those wires out as he can. Occasionally tying together the ones he physically can, to try and stop them from surging forward to imbed themselves back in his face.