Koji Nishio

Classic Tetris World Championship performance

Nishio was able to attend the Classic Tetris World Championship from 2016 to 2020, where he performed very well. In his debut to the tournament in 2016, he lost in the semi-finals to the eventual world champion that year, Jonas Neubauer in a 0–2 sweep.^[7] In the 2017 World Championship, he would qualify as the number 1 seed, but would lose in the second round to Alex Kerr, the eventual runner up. In 2018 he was noted as the favorite to win by Neubauer, and again qualified the number 1 seed.^[8] However, he lost in the semifinals again, this time to young Tetris prodigy Joseph Saelee, who would go on to defeat Neubauer in the finals, ending his streak of championships.^[9][10][2] This was Joseph Saelee's debut in the CTWC scene, who was notably also a hypertapper, being inspired by Nishio himself.^[5][11][12] The next year Nishio would reach the finals for the first time, where he matched up against Joseph Saelee again. Their match went to a game 5 decider, in which Joseph prevailed, claiming back to back titles.^[13][14][15] After these two tournaments, there was a massive influx of popularity, and more new players joined the community. The 2020 and 2021 CTWC would be held online due to the COVID-19 pandemic, and Nishio would participate in both. In 2020 tournament, due to its online nature, accommodated 64 players, double the previous year, separating them into group brackets A-H with a loser's bracket, Nishio made it to the finals of his group, but lost to the eventual champion, Michael Artiaga, also known as dogplayingtetris.^[16] In the 2021 tournament, which again features the group stage, Nishio lost in the first round, but was able to continue playing all the way to the finals of the losers bracket, where he lost.^[17] Nishio would return to the CTWC scene in 2025, having not attended a live event in the United States since the 2018 CTWC. He was able to qualify for the silver bracket, where he would make it to the quarterfinals.^[18]

Other notable accomplishments and records

Aside from the World Championship, Nishio has set multiple world records and other tournament victories. In June 2018, he set the score world record for NES Tetris with a score of 1,257,740.^[19][4] In August 2018 in Hong Kong, Nishio and Neubauer would play an exhibition game against each other, both being regarded as the best player of their respective countries. This match would go to a decider, and Nishio was able to win game 5 with a maxout score.^[20][1] In 2019, he would improve on his world record record with a score of 1,273,120.^[21][4] This score would eventually be beaten by Joseph Saelee.

During the years of 2018 and 2019, Nishio participated in the Classic Tetris Monthly Tournament 17 times, in which he won 11, include winning three in a row twice. In the other 6 tournaments he did not win, he came in the top four.^[22] His 11 CTM titles is tied for the record of CTM Masters victories. In 2023, he participated and helped cast the 2023 Waku Waku NES Tetris Festival in June 17-18th, 2023 in Ota City, Tokyo, Japan. He placed 3rd overall in the event.^[23] He would return for the 2025 edition, placing 5th, and helping commentate matches.^[24][25]

In November 2025, a Classic Tetris Friendlies match was made between Nishio and Saelee, who had taken a hiatus from Tetris. Saelee was able to win both matches in a sweep.^{[26][citation needed]}