It just happened.
It caught everybody off guard.
And Nick was in the middle of it.
Scanning the casino's lobby and watching as people scrambled to go out of the big doors all while dodging what Nick thought were other people but were those things.
Nick just stood there absorbing everything and quickly thought of a plan: Find a different exit outside, hot-wire the first car he sees, and drive the hell outta Savannah.
He thought it was a good plan but first things first he needed to find a way out without bringing attention to himself.
He walked around the lobby scanning the big room for a stairwell. Right hand on a pistol hidden in his suit. The thought of using it to kill those things made Nick uncomfortable.
He eventually found the stairwell and saw that it was already opened and also broken.
Great, he thought. He walked cautiously to the door and pushes it aside to make room for himself to get in. He peeked in the stairwell just in case.
Silence, other than a little alarm sound that was above the emergency exit door which was open as well.
Distant screaming brought his attention to the outside world. Nick mentally prepared him self for what he was going to see outside.
However, nothing prepared him for this.