[SPOILER] My thoughts, expectations, reactions of Amnesia.

[Alardem]

One thing I always in the game was: if the pigs were servants of the machine, then why were they attacking you before you fix it?

Blind instinct? Recognition?

But it's clear they know how to follow orders when the machine sends them into London.


Of course assuming you don't die in the game it could go like:

Engineer: "Okay piggies, when you see Mandus I just want you to chase him, and if you get close, give him a little tickle"

The Machine was effectively neutralized when it was sabotaged - Dark Mandus could communicate with the protagonist (as they shared souls), but from what I recall you only hear him screaming on the loudspeakers to the Pigs after activating the Reactor. The Pig-Men guarding the Machine wouldn't have known that Mandus was unknowingly helping them.

I still think that, as with Justine and her Suitors, the Man-Pigs recognize Mandus as responsible for their current condition and therefore worth a little revenge.