Bae "bengi" Seong-woong was given the starting jungle spot for SK Telecom T1 2, the new team built around Faker, in February of 2013. The team immediately qualified for their first OGN, attending OLYMPUS Champions Spring 2013 with high hopes. They shocked many by placing 3rd, losing 3-1 to MVP Ozone but beating CJ Frost in a clean sweep. After the tournament, their sister team, SK Telecom T1 1, disbanded and 2 was renamed SK Telecom T1. They came into HOT6iX Champions Summer 2013 with very high expectations and met all of them, reverse sweeping the KT Rolster Bullets 3-2 to take the crown and earn a spot at the Season 3 Korea Regional Finals. They were seeded directly into the finals, where they met the Bullets again and beat them convincingly, 3-1. They were the final Korean seed for the Season 3 World Championship but they still came in as the favorites to win the whole tournament. SK Telecom crushed the competition, ending with a record of 15-3 and clean sweeping Royal Club 3-0 in the finals and becoming the new world champions.
Before the start of the season, SK Telecom picked up a new team, eventually named SK Telecom T1 S, and the original team was renamed to SK Telecom T1 K. K continued their dominance by posting the best overall team performance in an OGN at PANDORA.TV Champions Winter 2013-2014 where they didn't lose a single game, culminating in a crushing 3-0 against Samsung Ozone. A few days later, the starting support, PoohManDu, retired and the team picked up Casper. This roster change would ultimately start the downfall of the team. A poor performance of the group stage led to a 3-1 defeat at the hands of Ozone in the quarterfinals of HOT6iX Champions Spring 2014. ManDu rejoined the roster and they were invited to All-Star Paris 2014 to represent Korea. With most of the team slumping, especially Bengi, it seemed as though K would lose the event. However they swept the tournament with a clean 9-0 record and dominated OMG in the finals. Morale was back up in the team when they returned to Korea to attend HOT6iX Champions Summer 2014. Unfortunately, they met Samsung White in the quarterfinals and lost to them 3-1 again. Regardless, they accumulated enough circuit points to attend the 2014 Season Korea Regional Finals. K had to play White again in a tiebreaker for the 2nd seed to worlds but were crushed 3-0 and forced to play the gauntlet. They were seeded directly into the finals but lost 3-1 to a red hot NaJin White Shield and missed Worlds.
Changes to the OGN rules forced K and S to merge to reform SK Telecom T1. Most of the original roster from K left the organization, with only Bengi and Faker remaining. The new team was invited to participate in SBENU Champions Spring 2015. In the middle of the season, T0M was picked up by the organization to be a substitute for Bengi. They swapped throughout the season and eventually made it to the finals against GE Tigers. Bengi did not play but the team dominated anyways and took the championship 3-0. SK Telecom's victory qualified them for the 2015 Mid-Season Invitational where they made it to finals but lost 3-2 to EDward Gaming. SKT placed first in the regular season of SBENU Champions Summer 2015 after only dropping one set the whole season. They beat KT Rolster 3-0 in the finals of the playoffs to qualify for the 2015 Season World Championship as the top seed from Korea. SKT was placed in a group at worlds alongside EDG, Bangkok Titans, and H2k Gaming. They went undefeated all the way to the finals, beating AHQ e-Sports Club and Origen in the playoffs along the way. They met the KOO Tigers in the finals and beat them 3-1 to give the organization its second World Championship.
SKT played in the 2015 LoL KeSPA Cup where they lost 2-0 in the semifinals to Ever. This series is widely considered to be one of the greatest upsets in League history.
During Champions Spring 2016, SKT used Bengi as their starting jungler in the first round robin. In March, SKT entered and won IEM Katowice 2016 without losing a single game. The team brought substitute jungler Blank for the tournament - Bengi did not play at IEM. During the second round robin, Blank was given the starting jungler position. SKT placed third in the regular season, earning themselves a spot in the playoffs. SKT then won the playoffs, winning their third championship in a row and for the first time a seed to the 2016 Mid-Season Invitational.
Their first place finish in the spring season earned them a spot in the 2016 Mid-Season Invitational. Notably, SK Telecom T1 were the only team to return to 2016 MSI from 2015 MSI. As the reigning domestic champions of Korea, SK Telecom T1 came into the tournament as massive favorites to win. However, their group stage performances were very lackluster as they dropped games to China's Royal Never Give Up, NA's Counter Logic Gaming, and two games to the LMS Flash Wolves. They ended their group stage with a 6-4 record, seeding them into the bracket stage at fourth place. Matched up against Royal Never Give Up in the semifinals, SK Telecom started to regain their form, beating them 3-1. They then proceeded to beat Counter Logic Gaming 3-0 to win the event and give them the trophy that barely escaped them last year. However, Bengi did not play at this tournament, as SKT preferred to run Blank as their starter.
During the 2016 LCK Summer Split, SK Telecom started to run Bengi in their games more frequently. Though they started the season strong, they floundered as the season progressed, leading them to start Blank more often. With a 13-5 scoreline in series, SKT placed second in the round robin, beating KT Rolster via game score tiebreaker. However, during the 2016 LCK Summer Playoffs, they met KT Rolster in the semifinals, where they were reverse swept 3-2 after going up 2-0 in the first two games. This gave them third place for the summer split. Combined with their first place spring finish, as well as the victory of the ROX Tigers over KT Rolster, SKT qualified to the 2016 Season World Championship on points as Korea's second seed.
At the 2016 Season World Championship, SK Telecom T1 were placed into Group B, along with LMS's Flash Wolves, NA's Cloud 9, and China's I May.