The agency formerly known as William Morris Endeavor is redefining the talent business, one acquisition at a time. It snapped up sports, entertainment, and marketing powerhouse International Management Group for $2.4 billion in 2014. In 2015 it closed a dozen more deals, acquiring Professional Bull Riders, which puts on—you guessed it—rodeos, and the Miss Universe Organization, which it bought from Donald Trump. The agency’s current valuation? About $5.5 billion. Last year it generated Ebitda of more than $400 million, thanks to its growing portfolio of brands—and megastar clients ranging from Tina Fey and Oprah Winfrey to Cam Newton and Serena Williams.