Took a Level in Badass: Sarah was initially a rather meek, quiet woman still suffering from the trauma of her losing her family. Over the course of the film, she finds new ways to deal with that trauma by turning into a killing machine.
Played By: Natalie Mendoza
Accidental Murder: While fighting off Crawlers, she reacts without thinking and kills Beth. Subverted in that Beth doesn't die right away, and Sarah eventually has to Mercy Kill her.
Jerkass: Holly is something of a loud-mouthed, insensitive asshole.
Too Dumb to Live: Her recklessness and tendency to rush forward blindly costs Holly her leg, and ultimately her life.
Vasquez Always Dies Is the most tomboyish of the group. Though technically she just dies first.
Wild Child: Absolutely; she's a hardcore 'sports fuck' who does basejumping and the like.
Played By: Craig Conway, Leslie Simpson, Mark Cronfield, Stephen Lamb, Catherine Dyson, Julie Ellis, Sophie Trott, Tristan Matthiae, Stuart Luis, Justin Hackney
I'm a Humanitarian: The Crawlers could technically be considered cannibals, as they are, according to Neil Marshall, evolved cavemen. There are several hints of this throughout the film.
Mama Bear: The first female Crawler seen in the film appears shortly after Sarah kills the Crawler's child. Upon learning that her child is dead (after a surprisingly sad moment of the Crawler desperately and pitifully nudging the body), she immediately goes berserk.
Morlocks: Cannabalistic subhumans living underground.