More than 25-thousand gamers have descended upon the city of San Francisco for the largest gaming development conference in the United States, known as GDC. Gamers have come from all over the world. CGTN's Mark Niu takes a look at why they're here and what they're working on.

It's been a wild ride for the game Fortnite, which allows up to 100 players to compete in what's known as a battle royale. In February, the game took in 126-million dollars from in-app purchases.

STEPHAN LEROUX GAME DEVELOPER "It's getting really popular -- the style, the work that's done in this game. I think it's starting to inspire a lot of developers."

Game evaluator Nathan Mark patrols the indie games section looking for what could be the next Fortnite.

NATHAN MARK SR GAME EVALUATOR, PEBBLE KICK "What we were looking for is especially for South Korea. Chinese games, a lot of them can also work for the South Korean market."

He soon likes what he finds in the three-on-three battle game Swallowed Star, created by Beijing developer by Fisher Yu, who's making his first trip to GDC.

FISHER YU CEO & GAME DESIGNER, DREAM JELLY "Our first goal is publishing in East Asia, and we also want to publish it in America."

While independent developers dream big, big companies like Epic and Tencent have joined forces with facial animation company Cubic Motion and motion capture company Vicon to wow the crowds with this. Actress Alexa Lee is projecting her voice, body movements and facial expressions into Chinese actress Bingjie Jiang. The digital human is called Siren. Everything happens instantly.

JEFFREY OVADYA MARKETING DIRECTOR, VICON "What we did was real time. It was happening live, which doesn't happen. When you play a game, watch a movie, you are talking about 2,3,4 years of post production work before it actually hits your screen."

ALEXA LEE ACTRESS "I'm not gonna lie. Yes, a little bit. The fact that I could drive Siren in real time. She looks similar to me. Her facial expressions are my expressions. That is kind of massively freaky."

DAVID BARON EXECUTIVE PRODUCER, CUBIC MOTION "Today, we've got Alex driving a female model but that could be a stylized character, a dragon, a dog, whatever. I could step in there and put the helmet camera on and drive the female character.

Fears that the technology could be used by politicians whatever that person said that."

DAVID BARON EXECUTIVE PRODUCER, CUBIC MOTION "We can do that. We could absolutely take a famous politician and drive them and put words in their mouth essentially. And I'm not going to comment on the fears behind that. But technically it's possible."

MARK NIU SAN FRANCISCO "With the incredible realism and motion capture technologies of today to the ability to play online with hundreds of players, sometimes it can be sensory overload. Fortunately, the Digital Game Museum is bringing us back to a simpler time. with many retro displays of old games. And how about this one Cocktail table Pong. Only 200 of them ever made by Atari. Three of them that we know of that still exist. This is one of them."

Locked in an old-school but still very intense battle at the Game Developers Conference. Mark Niu CGTN San Francisco.