And everyone, including newer outlets like Hulu and Apple, have been looking for the next “Thrones,” a series that can define a network, and help convince people to hand over $10 or $15 a month for subscriptions.

Three years after “Thrones” debuted, Netflix ordered its own high budget epic series “Marco Polo” about the Mongol empire (which was a flop). Amazon bought the TV rights to make a “Lord of the Rings” series and spent north of $200 million to do so (and still needs a script). Apple has a big-budget fantasy drama starring Jason Momoa and Alfre Woodard about what happens when to humanity after everyone goes blind (which still needs a premiere date).

There have been lots of mixed results so far.

“It has made everyone say, ‘O.K., where is our ‘Game of Thrones’? Which is the exact wrong way to find your next ‘Game of Thrones,’” said Casey Bloys, the president of programming at HBO. “Just to set out and say ‘Well we’re going to make our next “Game of Thrones,” we’re going to do a real giant show with a huge budget,’ well that doesn’t allow for all the other things that have to go right for a show to really resonate with a viewer.”