Accelerator's attention turns towards the boulders, narrowing his eyes suspiciously. Once they get close enough to see the glowing he's clicking his tongue. "The hell? Why are they glowing? Is this some kind of bizarre fluorescence?"

It's possible for rocks to glow, but normally they require some kind of blacklight. They don't do it under normal sunlight - at least, not to the normal range of human eyesight. And the rocks seem to be reacting to them (or at least, something), so is this something supernatural? Or magical? He isn't sure, but he doesn't like it.