Player profile: CoreJJ

corejj league of legends
Credit: Lol Esports Flickr

Who is CoreJJ

Jo Yong-in, better known as CoreJJ, is a professional League of Legends support player currently competing for Team Liquid in North America.

He was initially noticed by the public after signing as an ADC for Dignitas. During his first year as an elite player the team finished second to last in the LCS.

Despite the rough start, the South Korean organization Samsung Galaxy called him to join their ranks; with them CoreJJ started a successful career, becoming the only player to have starred in six consecutive world championships, winning one and getting silver in another.

Position and play style

CoreJJ currently performs the duties of a support in the bottom lane. His most relied upon characters are defensive supports like Braum, Tahm Kench or Taric.

When  CoreJJ fancies something more aggressive he tends to deploy Rakan, Zyra or Karma, although he is not defined by a particularly proactive style in lane; he would rather focus in protecting his ADC and waiting for the opportune moment to start a fight.

Praised for his mechanical skills, he is also capable of leading his team to victory.

Thus far, CoreJJ´s best champion by KDA and win rate in competitive play is Rakan.


CoreJJ´s career began with Bigfile Miracle as an ADC. With the team he competed in the 2014 Champions Korea, where he never got past the group stage, unable to win a single game.

After this brief episode in Korea, Dignitas hired CoreJJ for LCS, where his roster underperformed by finishing in the second-to-last position. It could have been worse for Dignitas considering that they were saved from demotion thanks to a miraculous reverse sweep.

CoreJJ´s second year with Dignitas, in 2015, was not noteworthy; CoreJJ and his teammates positioned at the middle of the table for the split, and during playoffs Dignitas did not advance past quarter finals.

After ending the year, the South Korean returned to his native region, this time with Samsung Galaxy, where he competed as ADC but later changed role to support; the roleswap turned out for the better, as CoreJJ went from being a middle-of-the-pack player to an elite one. The reason behind the swap was due to the arrival of Ruler, a brilliant marksman alongside whom CoreJJ would end dominating the bottom lane for years to come.

Yet CoreJJ had to spend some time adapting to his new position inside the team. The first few matches he played were all defeats, and it was not until summer that Samsung began to work like a well-oiled machine. They positioned fourth in their split, but when it came to the Worlds playoff they were came in strong, earning their qualifying spot. It was the first Worlds CoreJJ participated in, and fortunately he proved himself fit for the challenge. Samsung Galaxy advanced to the final, losing to a powerful SK Telecom T1.

With such good showings the team remained as it was for the next year. CoreJJ kept perfecting his new role, and by the middle of 2017 he was widely regarded as one of the best supports in the entire world.

After getting close to earning the LCK title in both splits, with a third and fourth spot in the spring and summer splits respectively, Samsung again qualified for Worlds in third place. During the tournament Samsung´s play impressed and they quickly became favorites to win. 

And so it was meant to be: Samsung got payback on SKT by breaking their hegemony by a 3-0 score (SK had won the previous two titles).

With such a tour de force here was CoreJJ, a powerful player that had gone from competing for the ninth spot in North America to winning the world championship in South Korea within a mere two-year time span. Still, the LCK was a title that resisted him.

Unfortunately, in 2018 Samsung Galaxy lost its identity; it went on to rename itself as KSV, then changing name again to that of Gen.G, and in the process the roster lost most of the distinctive leadership aura they had boasted of in the previous seasons.

Gen.G achieved two fifth places at the LCK playoffs. However, Gen.G still managed to secure a spot for Worlds, though this time the roster fell during the group stage, with only one victory and five defeats.

The loss was a hard blow for CoreJJ and the rest of the Gen.G members, who watched how their options to obtain a new title in Korea vanished. CoreJJ promptly decided to join Team Liquid in North America.

The bot lane that starred Doublelift and CoreJJ revolutionized the NA region in 2019. Team Liquid won two consecutive LCS titles with ease. In the MSI they fell in the finals to G2. CoreJJ, by then a common sight at Worlds, did not manage to carry his team past the group stage once again.

In 2020 Broxah arrived in the jungle, relegating the departed Xmithie and causing Team Liquid to end second to last in the spring split. The European jungler was not comfortable, and the team did not resume its march until summer, when Doublelift got replaced by Tactical.

Team Liquid sealed a great regular season with 15 victories and 3 defeats. Sadly, they finished third in the playoffs after a disappointing encounter against TSM, and, despite reaching Worlds, the team fell during the group stage.

2021 kicked off with a victory at the Lock In tournament of the LCS, a new preseason event created after a change in the North American league format.

In the spring split CoreJJ and his teammates finished second at the playoff, losing 2-3 against Cloud9. In the summer split they qualified for Worlds, this last one becoming the sixth competitive event he participated in; Team Liquid did not advance past the group stage.

CoreJJ would show good results with Liquid during 2022, winning the Lock In event at the LCS and the Spring split with a 14-4 score. During the playoff the team would fall against EG, getting a third place, and the same would happen during the Summer split. Sadly, CoreJJ and Liquid would not qualify for Worlds.

Fun facts about CoreJJ

  • CoreJJ holds the highest point record in the history of the North American League of Legends server, with 1751 points; this most likely makes him the highest ELO/MMR rated player in the history of the region as well.
  • CoreJJ´s name comes from the abbreviation of “Core Jangjeon”, a phrase from a character from Avalon Online which means “core charge”.
NameJo “CoreJJ” Yong-in

Source: Twitter
BirthdateJune 22, 1994
BirthplaceSouth Korea
TeamsBigfile Miracle (2014)
Quvic E-Sports (2014)
Dignitas (2014-2015)
Samsung Galaxy (2015-2017)
KSV eSports (2017-2018)
Gen.G (2018)
Team Liquid (2018- present)

Also available in: Español

Ricardo Hernandez

Ricardo Hernandez

bwipo league of legends
Player profile: Bwipo

One of Europe´s best, Gabriel Rau, better known as Bwipo, is a professional League of Legends competitor

showmaker league of legends
Player profile: ShowMaker

Faker´s heir apparent, ShowMaker is a young mid laner who has already left his own mark in competitive League of Legends

League of legends Faker playing for SKT
Player profile: Faker

The most famous player in all of League of Legends, we explore the story of one of esports greatest titans

hylissang league of legends lol
Player profile: Hylissang

“Agressive” and “support” are not terms that always pair well in League of Legends, yet Hylissang proves they can work spectacularly together