Deckard vs Batty

The scene starts with Batty looking in on Deckard, kept out by a fence but telling Deckard that he can see him. This to me represented the Nexus 6’s plight overall: they are tantalizingly close to being completely human, but lack the empathy necessary to pass. As the scene progresses Deckard and Batty are shown to be going through similar things. Both are living in fear of death, Deckard from death by Batty, Batty from death by degeneration. They both are portrayed with animalistic qualities. Deckard flees from Batty looking like frightened prey, while Batty looks almost rabid, perhaps mad with the thought of his inevitable death. Batty’s lack of rationality becomes literal when he sticks his head through a wall and speaks nonsense to Deckard. Deckard, in turn, acts like an animal trapped in a corner. He knows attacking Batty physically will not go well, but he does so anyways, mostly because he has no choice. He, unlike some of the replicants, shows a strong survival instinct.  Batty, for his part, lets Deckard go, like a cat that wants to play with its food. The heavy rain and the flickering light coming from lightning both contribute to the impression that Batty has gone insane. The viewer is led to believe that Batty has lost it, but as is revealed in the end, Batty is in full control this entire time. He merely wants Deckard to know what living in fear is like.