Starscream grabs his attention the moment he nears in his jet mode - the sound of turbines are difficult to miss. Shockwave still draws power to his cannon even after the telltale sound of transformation, out of caution, mostly. He has cables buried into the data tower with information dancing across his vision. He wasn't exactly in a defensible position.

When Starscream is the one that slips out of his earth jet mode, the weapon lowers. There's a slight rise of the shoulders, a slight tilt of the helm that said Starscream was the last person he wanted to meet right now. Gross.

"You survived," he adds coldly, referring to the last battle in which Starscream mysteriously disappeared while it went to shit. Again.