At base, Parker's a primitve animal of a person, but in this one he's unusually savge and driven by emotions, mostly rage and a desire for payback, that he doesn't really understand. That doesn't stop him killing a bunch of folks and threatening a few men and women - Stark does not hold back, he's an abusive asshole - but the tight plotting that goes on to characterise the series is there as well as indications of the cool machine that's Parker's more usual state.