South Korean giants T1, led by "Faker," won their fifth League of Legends world championship crown in London on Saturday, beating China's Bilibili Gaming in a thrilling final.

The teams were locked at 2-2 at a packed O2 arena, but T1 clinched game five to make it back-to-back titles after nearly four hours of tense action.

China's BLG started strongly, taking the first game before T1 struck back to level.

The Chinese team pulled ahead again at 2-1 only for their opponents to hit back again and go on to take the decider.

Faker, who won the MVP award, was asked what message he would send to himself 11 years ago, when he clinched his first world title.

His response was just, "Have fun."

For the third year in a row, the five players on the team were the same: Zeus, Oner, Gumayusi, and Keria, accompanying Faker.

The 28-year-old, whose real name is Lee Sang-hyeok, is a multi-millionaire eSports superstar in South Korea who has been given the title of "national treasure.".

Even though the match started around midnight in South Korea due to the time difference, hundreds of dedicated T1 fans gathered at LoL Park, an eSports venue in central Seoul, to cheer on their beloved team. 

The crowd erupted in cheers when Faker appeared on the screen. 

"T1 is the most special team because it makes things happen when everyone else says it's impossible," said Lee Pari, a T1 fan. 

Hundreds of Chinese fans arrived early for a watch party in a shopping mall in Beijing.

Cosplayers dressed as characters from the game posed for photos on the steps leading to the entrance.

Inside, fans were packed shoulder to shoulder an hour before the first round.

Cheers filled the room when BLG players appeared on the screen, and periodic chants of "BLG! BLG!" rang through the mall.

Speaking after the match, 19-year-old student Du Zhaoyan said he had not expected BLG to lose.

"I thought they could win, and I wasn't planning on going back to school tonight," he said. 

"I was going to go out for a drink with people who were also watching the game tonight and stay out until sunrise before going back to school. So now it feels a bit depressing to leave."

But engineer Zhao Lingling, 26, said she was a Faker fan.

"I'm very happy to see him win his fifth championship," she said. "He played very well tonight, and his fourth game was very impressive. (China's) Bin also played very well. I hope to see Faker again in Chengdu next year."

The goal in League of Legends, which pits two teams of five against each other, is to destroy the enemy's base, known as the Nexus.

South Korea has traditionally been a League of Legends powerhouse, but in recent years, Chinese teams have been growing stronger.