Adrien Brody as Royce
An ex-military soldier turned mercenary who reluctantly assumes leadership of the group of humans.
Brody claimed he had been "blown away" by Predator and viewed his role as a challenge, wanting to bring a complexity to the character that would contrast with Schwarzenegger's role in the original film.
He did put on twenty-five pounds of muscle for the role, stating that "I want it to be entertaining and part of the ride that people see when they see a movie like that. But that's not really why I'm in it and that's not really what I brought to it. I brought the same kind of discipline that I would to a film like The Pianist."
Antal and Rodriguez specifically wanted to avoid casting an actor physically similar to Schwarzenegger, wanting to "go in a very different direction" and reasoning that real-life soldiers are wiry and tough rather than burly.
"We thought casting a physically 'Schwarzenegger-esque' character would have done the original film a disservice", said Antal, "and would have done this film a disservice because we are not trying to remake or copy the original film. I told everybody early on that I can make anybody look tough. What I can't do is teach them how to act".
Alice Braga as Isabelle
A sniper from the Israel Defense Force. She failed to save her spotter during a mission, and feels that she has been brought to the alien planet as punishment and to seek redemption.
As the only female character, Isabelle plays the role of peacemaker: "My character, funny enough," said Braga, "is the one that is always trying to grab everyone together and like reuniting everyone and stopping the fights and saying that we have strength in numbers."
Braga described the character as "a tough cookie ... sweet inside but tough outside". She read a sniper manual to prepare for the role, and carried a fourteen-pound sniper rifle during shooting.
Topher Grace as Edwin
A doctor who does not seem to belong amongst the group of hardened killers until he reveals that he is a psychopathic murderer.
Grace was dubious about taking the role when he read the script, "because I really liked the first Predator, but all the sequels haven't been as good. Then when I read this, I thought, 'What Aliens was to Alien, this is to Predator'. Because Predator never really got its due; it never really got that sequel."
He compared Antal's approach to that of James Cameron, director of Aliens; remaining faithful to the original work but taking the concepts in slightly different directions. Grace performed some of his own stunts, including jumping off of a waterfall.
Walton Goggins as Stans
A death row inmate from San Quentin State Prison who was scheduled to be executed in two days before suddenly finding himself on the alien planet. Responsible for 38 murders and also strongly implied to be a rapist.
Oleg Taktarov as Nikolai
A Russian commando from the Spetsnaz Alpha Group who was fighting in Chechnya before finding himself on the alien planet.
Taktarov, a retired mixed martial artist and former Ultimate Fighting Champion, described his role as combining elements of Arnold Schwarzenegger, Jesse Ventura, and Bill Duke's characters from the original Predator film, and praised it as "the first time you get a really, really, positive, good Russian character in an American [film]".
Taktarov used his martial arts training during some of the film's action sequences. While filming a scene he hit his face on a steadicam and was bleeding, but continued filming because the blood added to the effect of the scene.
Louis Ozawa Changchien as Hanzo
A Yakuza enforcer who rarely speaks and reveals late in the film that he is missing his leftmost two fingers, having performed yubitsume.
"I guess he used to be a guy who can murder someone without a qualm," said Changchien of the character, "but by the time he arrives on the alien planet, he'll no longer be that kind of person. Those things aren't explained in the script, but you'll get it when you see the movie."
Changchien used his kendo training for a scene in which his character uses a katana in a duel against a Predator. Antal, a kendo fan, insisted that the swordfight look authentic.
Mahershalalhashbaz Ali as Mombasa
A Sierra Leone Revolutionary United Front death squad soldier.
Danny Trejo as Cuchillo
A ruthless enforcer for the Los Zetas Mexican drug cartel who carries twin submachine guns.
Laurence Fishburne as Noland
A United States Army Air Cavalry soldier who has survived on the alien planet for multiple hunting cycles.
"It's a really interesting role," said Fishburne, "quite different from Morpheus [from The Matrix]. He's a bit shady, crazy, surviving on his own, kind of a ratty character."