The International 2021 took place throughout October 7-17 with 18 participating teams and over $40,078,195 prize pool. The venue for the annual tournament was Bucharest Arena Nationala. Teams played on Dota 2 patch 7.30d.

The tournament was held by Dota 2 publisher Valve and tournament organizer PGL.

The event had participating teams from different DPC regions, including North America, South America, Western Europe, Eastern Europe, China and Southeast Asia. The event was divided in 2 parts — the group stage, going on from October 7 to 10 and the main event, happening from October 12 to 17.

The winner of the tournament was the CIS team Team Spirit, which defeated PSG.LGD in the TI 2021 finals. Spirit came to conquer the International Stage from the lower bracket of the event, while PSG.LGD had better results and were considered the favorites of TI 10.