Sumail Hassan was born in Pakistan on February 13, 1999, as the son of Syed Tatheer Mumtaz and Syeda Zill-e-Huma. He has a brother, Yawar Hassan, who also plays professional Dota 2. Sumail first started playing Dota when he was seven years old. Upon his arrival to America he began playing in the North American Elite League. Hassan quickly became the highest rated player in the in-house league, establishing himself as one of the best unsigned talents in North America. Evil Geniuses (EG) signed him in January 2015, joining Fear, Aui 2000, Universe, and ppd. A month later, EG and Hassan participated in the Dota 2 Asia Championships, where finished in first place. EG’s captain ppd entered the tournament with a focus on drafting around him. Sumail’s breakout performance at the tournament led to widespread recognition as a young prodigy in both the Chinese and English Dota scenes.

Hassan’s professional career began when he signed with Evil Geniuses in 2015. That same year, he and the team won The International 2015, which awarded him over a million dollars in prize money. He spent the next four years with the team, having varying degrees of success. In 2019, Hassan left EG to briefly play alongside his brother on the Quincy Crew before briefly signing with OG in 2020.

EG entered The International 2015 as one of the tournament favorites. However, EG experienced a setback of their own after losing the upper bracket finals 0–2 to CDEC Gaming. EG defeated LGD Gaming in the lower bracket finals and prevailed 3–1 in a rematch with CDEC in the grand finals to win the tournament and a US$6.6 million grand prize, which made Sumail the youngest player ever to surpass a million in esports winnings. In 2016, Sumail was named by Time as among ‘the 30 Most Influential Teens’ that year. In September 2019, it was announced that he would be leaving the team to join the Quincy Crew alongside his brother Yawar. However, he left the team after only a few weeks, with the team’s manager claiming he was not a “good fit” for them, before signing with OG in January 2020. Shortly after, he was removed from the team after 6 months.