OpenAI Five: The International 2018 Results

OpenAI Five competed against world-class professional Dota 2 players at The International 2018, demonstrating the ability to play high-level, competitive games despite losing both matches. This event served as a critical test of the AI's capabilities when facing elite human competition under standard game rules.

Match Results and Competition Level

OpenAI Five faced opponents significantly more skilled than those in previous benchmarks. The AI played two primary matches against elite professional teams:

• paiN Gaming: Five played against one of the top 18 teams globally. Despite a strong start for the human players and a mid-game recovery by the AI, the match lasted 51 minutes before Five lost to high-level strategic pushes.
• Chinese Superstar Team: Five faced a team consisting of players like Xiao8, BurNIng, ROtK, Ferrari 430, and SanSheng. Three of these players had previously competed together on a professional team, and the average tournament earnings for the players in this match were approximately $1 million per person.

After a series of exciting back-and-forth teamfights, Five lost this second match after 45 minutes.

Transition to "Real Dota" Gameplay

To align the competition with what professional players consider "Real Dota," OpenAI removed a major restriction used in previous benchmark games.

The Courier System Change

In previous benchmarks, each hero was assigned its own invulnerable courier for item delivery. This system allowed OpenAI Five to develop a high-pressure playstyle because heroes could receive regeneration items constantly without retreating to heal.

In the International 2018 matches, the AI transitioned to using a single mortal team courier, which is the standard in professional play. OpenAI began training the model with this single-courier system six days prior to the event. While this change was expected to temporarily decrease performance, it was implemented to ensure the gameplay was more authentic and exciting for observers.

Technical Analysis and Future Directions

OpenAI stated that the courier system change was not the primary cause of the losses. Instead, the team identified the need for further training, bug fixes, and the removal of remaining scripted logic within the model.

Beyond the specific goal of winning at Dota 2, OpenAI views the development of OpenAI Five as a means of building AI technologies in a safe sandbox. The project aims to use the lessons learned from these complex environments to inform the development of future advanced AI systems that are safe and beneficial to humanity.