These early test cores have so much animation to them. I wish we at least got to see one of these types in the retail version of portal 2. Guess we have mods for that though. (And fan animations)
Pretty sure a few of her voice lines here are her playing back a memory of people's deaths. The scream before she said what was that, would have been people dying to the toxin, while she mocks them. And her screaming after asking if anyone smells something is burning would likely be Caroline being put into glados, as a smell of fire is a sign of damage to the brain or nervous system, hence how glados knew the core change would be painful.
