Дін Dy Сунь is a Chinese Dota 2 esports player. He is the champion of DreamLeague Season 11: The Stockholm Major and EPICENTER Major 2019. His signature heroes are Disruptor and Grimstroke.

Dy began his professional career in the fall of 2017 with Vici Gaming Potential. Playing in the fourth position, he and his team earned gold at Dota2 Professional League 2017 S2: Secondary. In September 2018, Dy was promoted to the main roster of Vici Gaming, where he became the captain. In their first major tournament, ESL One Hamburg 2018, the team reached the finals but lost to Team Secret. After placing 7th-8th at The Chongqing Major, Vici Gaming won the StarLadder ImbaTV Dota 2 Minor Season 1, DreamLeague Season 11: The Stockholm Major, and EPICENTER Major 2019, securing a direct invitation to The International 2019 (TI9). At the tournament, Dy and his team finished in 5th-6th place.

In the 2019-2020 season, Vici Gaming expressed their desire to win The International 2020, earning silver at the MDL Chengdu Major and bronze at DreamLeague Season 13: The Leipzig Major. However, the tournament was postponed due to the COVID-19 pandemic, and the world entered the era of online competitions. Over the course of six months in the Chinese leagues, under Dy's leadership, the team consistently achieved prize-winning placements and occasionally emerged as champions, such as in OGA Dota PIT 2020 Online: China and OGA Dota PIT Season 3: China.

When the new DPC season was announced in January 2021, Vici Gaming showcased themselves as favorites in their region, twice earning bronze in Valve's leagues and placing fourth at the WePlay AniMajor. Many analysts believed that it was due to the performances of Pyw and Dy that the Chinese team secured their spot at The International 2021 (TI10). After the WePlay AniMajor, the players returned home, competed in several Chinese tournaments, and then headed to Europe in September 2021 to prepare for the biggest tournament of the year. At the championship, the team finished in 5th-6th place, earning over $1,400,000 in prize money. Afterward, Dy and Pyw transferred to Xtreme Gaming.

Dy with Xtreme Gaming achieved 2nd place at Intel World Open Being, championship at OGA Dota PIT Season 6: China. There was also a 2nd place at the Chinese qualification for The International 2022 (TI11), went to the Last Chance Qualifier, where he placed 5th-6th. 

In 2023, Dy with Xtreme Gaming could only qualify for 1 Major tournament out of three possible tournaments - ESL One: Berlin Major 2023, with 15-16th place at Riyadh Masters 2023. In August, Dy loses to Azure Ray and Xtreme Gaming takes 2nd place at the qualification for The International 2023 (TI12). After this result, Dy leaves the pro scene and focuses on streaming. 

In December 2023, Dy returns to the pro scene. He joins the new Xtreme Gaming roster.

The new roster started the year quite successfully: 1st place at Elite League 2024, 3rd at DreamLeague Season 22 and 2nd at PGL Wallachia Season 1. Also, Xtreme Gaming participated in DreamLeague Season 23, where they took 4th place.

In the summer, the team competed in the Riyadh Masters 2024, finishing 8th and not achieving significant results. In August, Dy participated in the Clavision Snow Ruyi Invitational, which took place in China, the homeland of Xtreme Gaming. In this tournament, the team took first place, defeating Team Spirit in the grand final.

At The International 2024, Xtreme Gaming took 5th-6th place, losing to Tundra Esports in the lower bracket of the playoffs.

In October 2024, Dy announced his retirement as a professional player, but in November he joined the Gaozu pack and participated in ESL One Bangkok 2024, where he took only 9-12th place.

In May 2025, Dy returned to Vici Gaming. In October, the team competed at FISSURE PLAYGROUND 2 but failed to advance past the group stage.

On December 12, it became known that Dy left Vici Gaming.

At the end of December 2025, it became known about the formation of a new Chinese team Team Refuser, which Dy also joined.