Seeing as how Jok was already surveying his current location, which involved the fairly standard technique of checking your corners, or rather looking left and right, he immediately noted his opponent’s sudden appearance eight meters away off to his right in his peripheral vision. If they hadn’t been in such an empty room he might not have been such an easy spot, but they were, and so it was.

Jok span around and fired in the same movement, sending a spray of deadly SMG rounds across the bare eight meter gap between the two of them as he centred in on his foe. Even as he initially turned around at least two of his four shots were roughly on target centre of mass, and as he continued to unload from the hip with a practiced ease an increasing amount of rounds would be on target and heading straight for Vos. The SMG barely moved in his Exo-suit supported arms, and the sound was negligible due to the silencer despite the nature of their location. 

If his opponent moved towards him Jok would obviously shift his aim and continue to fire, the automatic function of his weapon designed for close quarter clearance such as this providing him with ample opportunity to end the fight with one quick fusillade of deadly fire.