...Odd. Aside from the usual gentle hum of machinery and the occasional hiss from the air vents, the Hall of Doom is usually rather quiet. But there's a noise echoing through the narrow underground corridors. And as the Riddler draws nearer to the small little room, fingers cautiously curled around his cane as he stands, framed, in the doorway... he recognizes it.

It's the sound of Edward's own voice.