>>106104612That's because it wasn't Pyg. It was Bruce tripping on some grade A acid and hallucinating that Damian was Professor Pyg. If you look at the body language, particularly during the fight scenes, and compare it to when Damian fought the fake Batman in Death of the family you'll realize it's the same choreography.
The butcher knife is the antidote Damian is trying to inject. The bow Pyg gives is the same one Damian has given Nightwing when he's appeared in the Seely run. The carving off a piece of the hog corpse and garishly eating it before stabbing it with the knife while talking was Damian taking the antidote to show it's safe and reloading another dose for Bruce.
His throwing the quote about the little pigs back at Bruce is actually pretty tame for a pissed off 13 year old, any 13 year old. Insanely tame for one whose father has just ranted about being still upset over being left at the alter, which in universe means Bruce was more traumatized by that than Damian's death. Hence his little huff as soon as Bruce starts sobering up, especially in light of how Bruce has never really let Damian in despite Damian's efforts, but let Selina in despite their history of her betraying him and choosing one more job, another scheme, one more break in over going straight.
Basically this issue is the explanation for what's happened/happening over in Teen Titans where Damian has started crossing lines, albeit nothing Bruce hasn't done himself in canon multiple times including Rebirth, and would rather die than speak to or see his father again. Just like the failed wedding is why Bruce went overboard on Jason, which if everyone is paying attention, what happened there and in Batman with the Penguin is also part of Bane's overarching plan that started with bombing the orphanage that Selina and Holly grew up in.