The 10 members of Gen X range in age from 33 to 52, while the Millennials are between 18 and 31.
The show is taking the competition to Fiji for the second time this season and according to Probst, some of the generational divides came into play just days in.
"Some of the Gen Xers have kids that are Millennials, so there's this parent-child thing that you can't avoid, because they're parents and they're imagining, 'What if this was my kid out here?'" he says. "We've already had some rough weather and I know already in talking to Gen X there was some concern for those kids."
While the location presents unique challenges in weather, it also provides a big opportunity for Probst.
"I'm happy to be back in Fiji to re-write the Survivor history in Fiji," he says. "I've always been honest: Fiji was not one of my favorite seasons. Doesn't mean the people weren't good. Doesn't mean I don't like Earl as a winner. I think he's a great winner. But as a season -- not one I'd put in my top 10. We're determined to make this a top 10 season."
Check out the cast stats below.
"VANUA" TRIBE -- MILLENNIALS
Lives in: San Francisco
Occupation: Homeless Shelter Manager
Lives in: West Hollywood, Calif. via Brookline, Mass.
Jessica "Figgy" Figueroa
Lives in: Nashville, Tenn. via Indianapolis, Ind.
Justin "Jay" Starrett
Lives in: Fort Lauderdale, Fla.
Occupation: Real Estate Agent
Lives in: Los Angeles via San Francisco
Occupation: Professional Gamer
Lives in: Fort Worth, Texas
Occupation: Vacation Club Sales
Lives in: Yakima, Wash.
Occupation: Missionary Recruiter
Taylor Lee Stocker
Lives in: Postfalls, Idaho via Spokane, Wash.
Occupation: Ski Instructor
Lives in: Long Valley, N.J.
Occupation: High School Student
Lives in: Brooklyn, N.Y.
Occupation: Asset Manager
"TAKALI" TRIBE - GEN X
Lives in: Dedham, Mass.
Occupation: Police Sergeant
Lives in: Moore, Okla.
Occupation: Trial Lawyer
Ciandre "CeCe" Taylor
Lives in: Granada Hills, Calif. via Buffalo, N.Y.
Occupation: Insurance Adjuster
Lives in: Sherman Oaks, Calif. via Philadelphia, Penn.
Occupation: Television Writer
Lives in: Voorheesville, N.Y.
Occupation: Assistant District Attorney
Lives in: Denver via Hana, Maui
Lives in: Diamond Bar, Calif.
Lives in: Sugarloaf Key, Fla. via Long Island
Occupation: Boat Mechanic
Lives in: Los Angeles. Originally from Honolulu, Hawaii.
Occupation: Recruiting Director
Lives in: Otsego, Minn.
Occupation: Youth Pastor
Survivor: Millennials vs. Gen X premieres Sept. 21 on CBS with a special 90-minute edition.