I'm not 100% sure if that's PhysX or not. Maybe not as isn't PhysX an nVidia thing and these consoles are AMD.
I can't recall seeing the breathing effect on the PS3/Xbox 360 versions but it was there on PC.
I've had a quick read, other things to look out for are fog which reacts when characters move through it, pieces of paper flying about instead of just being static stacks, exploding floor tiles.
I personally thought the chest thing was basic animation?... I've seen papers flying about walking over them. Haven't paid attention to the exploding floor tiles or the fog.
This game is starting to make me think of The League of Extraordinary Gentlemen with these morphing mutants.
I seem to be coming across more and more heavy battles? Loved that section for apprehend Harley with the electrocution floors as one or two thugs got caught out on it. Each section cleared 5 - 7 thugs came out and a few with those shock sticks?
Had seen cell 3 frozen in ice...