Stark couldn't hear Soulayer's steps, but he could imagine them near him as the boss searched the darkness for any signs of the boy.
He was in an enraged state, and wanted to end this battle as soon as possible: he didn't like to torment the souls, but they were needed for his victory this time.
On the other hand, Stark still had his eyes closed, focusing his attention on whatever he needed to do to survive this situation.
[Focus… and create the image of the enemy inside your head…]
He imagined Soulayer's figure in the spot it was in right before using [Eternal Darkness].
'It's working…!' Stark was surprised as even though he had his eyes closed now, he could actually see Soulayer right in front of his body, although that was just a copy from his imagination he wanted to use.
[Now… think of all the possibilities…]