Other mistake: Neither Edward nor Bella are sparkling at the very end of the movie in the sunny scene in the meadow of purple flowers, as the vampires are supposed to. (01:40:00)
The Twilight Saga: Breaking Dawn - Part 2 (2012)
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Directed by: Bill Condon
Starring: Kristen Stewart, Robert Pattinson, Maggie Grace, Taylor Lautner, Peter Facinelli
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More mistakes in The Twilight Saga: Breaking Dawn - Part 2
Bella Swan: You nicknamed my daughter after the Loch Ness Monster?
Question: Can vampires and werewolves be killed or injured by anything other than vampires and werewolves?
Answer: Sure. The problem is that these films portray vampires and werewolves as having super-human abilities, so it'd be significantly harder for a regular person to kill one. But nothing about the films seems to indicate it's overtly impossible.
Answer: Aro also makes the argument that for the first time in our history humans pose a threat to our kind with their weapons that can destroy us. Theoretically any weapons that can tear apart and/or burn the vampires would work. So, yes, things other than vampires and werewolves can kill the vampires and werewolves.