He was getting closer as the gunfire began coming in on his location.  It was targeted but not exactly precise as he raises up the Aegis Shield to protect from any stray shots that might actually be on target.  Luckily doing so as rounds do end up striking their mark impacting into the shield creating dent after dent as Enki keeps pushing forward.  The shield can repair itself from the damage but only if the strikes against it would stop and that seems to not be happening any time soon.

Having already focused the Howlingsteel materia in his blade he has to strike back but with expert timing.  A bullet smacks into his shield again and with the fraction of an opening his shield moves to the side to let him swing the blade forward sending out a small horizontal slash that produces an arc of magical origins.  Taking on the properties of the materia, the arc is more like a steel blade than a condensed form of energy.  What sets it apart is the loud humming coming from it as it vibrates through the air.  As it heads towards where the gunfire is coming from the closer it gets the louder the person firing their weapon on the other end will hear it.  The vibrations of the sound waves will effect the surroundings of the traveling blade pushing the burning leaves back and forth at first where it was launched, but the closer it gets to the gunman they will notice the wood from the trees splintering near it splintering and if any branches would get in the blades the path they would be moved or shattered in similar ways allowing the arc to travel unhindered.  

If for some reason the arc would hit him, whatever armor he would be wearing would be at first hit with the sonic vibrations the blade would put off and then be struck with the cleaving edge of it.  The sound of the howling slash would leave anyone deaf blowing out ear drums if there was no ear protection being worn at the time.  The speed of the arc the gunman would find to be comparable to his own bullets, but the size of it would give them some advanced notice to try to do something about it, even though dodging the blade would be easy the deafening sound and its sonic pressure would likely still effect them.

Quickly and still moving forward Enki moves the shield back to his front after the slash was unleashed, the Aire Tam Storm in its basic sword state and not the great sword form meaning the strength of the attack could have been much worse.  Knowing not to play all his cards out right away but also knowing he must prepare something else to help close the distance between him and the gunman he has the Gilgamesh arm prepare the Odin materia inside of it for use as he leaps through the last shrubbery and onto the street where the real battle will commence.