I like the thought that Croc's body has a kind of 'give' to it, like pushing in on a sandbag might or that sinking feeling you get when you squeeze a stress ball. He can control it, for the most part, and he's normally pretty firm muscle under his layer of fat, but if he's distracted or relaxed enough his control kind of slips away, you could probably press into him and leave a divot.
You could also literally sink into him like quicksand if he's loose enough. Imagine like falling into a grain silo.
