The world of League of Legends esports exploded over the weekend as G2 Esports toppled Royal Never Give Up, the team that was seen as the shoo-in champions. And a day later, Cloud9 took down Afreeca Freecs, ending South Korea’s five year reign over Worlds.

Twitter was a flood of baffled cheers and memes. The League of Legends subreddit had back-to-back threads filled with all-caps comments rejoicing over the two winning teams.

Casters and analysts around the world were taken off guard by the upsets.

This was the reaction from Spanish casters to G2 Esports’ final game against RNG.

And when Cloud9 scored its third and decisive victory over Afreeca Freecs, the livestream caught NA LCS caster Kobe’s voice cracking, and him wiping his eyes.

But all the excitement isn’t for the Grand Finals of Worlds 2018 -- it’s just for the Quarterfinals. There are still many days to go before a team can be crowned champions.

So why are these two wins so significant and so emotional?

Because this top four team lineup marks a new historic moment in League of Legends.

This is the first time a North American team has reached the Semifinals of the World Championship.

A happy family photo of Cloud9. (Picture: Riot Games)

This is the first time that there won’t be a South Korean team at the Finals since 2012.

G2’s 3-2 victory over RNG is one of the most stunning and unexpected upsets in League of Legends history.

Both the NA LCS and the EU LCS have long been seen as the weaker regions compared to China and South Korea.

The Western teams would go to South Korea for bootcamp to hone their skills and prepare for major competitions. North America in particular had the reputation as the region who would sign brilliant, skilled individual stars onto their rosters, but then fail to perform well in international tournaments.

It seemed like the LCS teams would often have to find talent from the other regions in order to win.

But over the weekend, both G2 and Cloud9 showed that they can win on the international stage with their homegrown players, some of whom are untested rookies, and beat out the Chinese and South Korean giants.

For NA fans in particular, this is the first time they’re able to root for their own region.

This was the ultimate underdog victory

Both Cloud9 and G2 Esports were the third seed of their regions going into Worlds.

They were seen as the worst teams out of the Western ones at Worlds.

But the gauntlet run, the Play-Ins, and then the Groups Stage brought out a better, more confident level of play in both teams.

Perkz in particular was highly praised for his skilled mid lane plays. (Picture: Riot Games)

This was supposed to be China’s year to dominate the competition, with Royal Never Give Up taking the crown. RNG were the Mid-Season Invitational 2018 champions, the Rift Rival 2018 champions, and their ADC Uzi was widely praised as one of the most formidable opponents in the competitive scene.

So even after G2’s steadily improving performance in Groups Stage, analysts still say RNG had the more powerful team fighting roster and the more skilled players. ESPN’s predictions for the Quarterfinals acknowledged G2’s ability to surprise, but thought that RNG would still make short work of them.

But G2 outplayed the world champions, punishing them for depending too much on Uzi, punishing them for ignoring the fog of war, and punishing them through skillful use of game mechanics.

While some cautiously thought Cloud9 should be able to match South Korean team Afreeca Freecs in skill and teamfighting, history still gave many NA fans pause. No North American team has ever beaten a Korean team in a best-of-five at Worlds.

But now Cloud9 has set a record.

Invictus Gaming is the last Chinese team left in Worlds 2018. They will be facing off against G2 on Saturday, October 27. Cloud9 will be playing against Fnatic on Sunday, October 28.