The second group: They are the disbelievers, the disobedient and the wrongdoers who had gone against the true path and the true call. They will be in the opposite state. This is because, they have now witnessed with their very own eyes and have acquired knowledge and certainty that they used to deny the noble Prophet and the verses of Allah (swt). They are thus taken by surprise that the Day of Judgement and Recompense are true.
Thus, their faces blacken. Their faces are covered by dust and blackness due to the great terror.