OpenAI Five at Dota 2 – The International [video]

> I don't know OpenAI selected it, but it's highly conducive to OpenAI Five's strengths--deathballing, mechanics, teamfight coordination, etc. It lacks essentially all of the heroes that humans would normally pick to counter that strategy.

Isn't it the other way around - openai adjusted to the hero pool to come up with its' strategy, because it was trained on this hero pool.

If hero pool had only late-game melee carries - I assume openai would come up with a strategy that works with that.

So three major differences between this and the last big match for OpenAI Five which explain the different result in favour of the Humans:

1) The Humans, Pain Gaming, is a professional team with players that regularly play and practice together and attend major tournaments. While they are the weakest team at this event and are arguably there only because of a regional qualifier system (they are from South America and the strongest team in an up and coming region), they are capable of taking games off some of the strongest teams due to their unpredictable and dynamic play. They are substantially better than the team of ex-pros and commentators that last played against the AI.

2) They removed an important limitation in the game, which was the 5 invincible couriers, and replaced it with a single killable courier that the five agents have to share (just like in a normal game of dota). The AI was able to use the single courier effectively, but did occasionally let it die a bit too often. What is important about this change is that it invalidated a strategy of the AI which was to continuously ferry consumable healing items to enable relentless aggression after gaining a slight edge in the early game. The AI adapted to this change by playing more cautiously in light of this standard resource/logistics constraint. It adds strength to the argument that as the OpenAI team introduces more complexity and resource constraints back into the game that the AI's weaknesses start to become more apparent and exploitable by better players.

3) The heroes composition was drafted in advance to be as even a match as possible, and a coin flip was made to decide which team got which draft. This is important as the version of the game is a subset of the game, and the humans evidently didn't understand the meta game in this weird subset during the last event. From the AI's perspective this was as even a draft as possible given the very small hero pool. In the last event the AI predicted 70-95% win confidence before the game even started due humans not understanding the drafting meta with a pool of 18/115 heroes and no bans.

Still, really impressive performance by OpenAI as at least for the early game and some of the mid game it was a close game with lots of good plays by both sides. The fact that OpenAI can be comparable to a pro team in what is nearly a full game of dota is really impressive.

It's five different instances:

https://openai.com/five/#how-openai-five-works

5 separate bots.

There are a lot of areas that OpenAI needs to improve on. the bots generally;

1. terrible at warding and dewarding

2. are terrible at using spell spam to farm. while their aoe spell usage is great in team fights, they suck at using spells to farm when they are alone. Gyro used his ult to farm a normal sized lane and still missed half the creeps.

3. don't understand bouncing spells like the lich nuke. In fact many times lich used that spell as a poking spell.

4. Bad at non-nuky/long running ultimates. DP made really bad usage of her ult several times outside of team fights.

5. Bad at judging Roshan respawn.

6. bad at using ability runes.

7. Are bad at juking. They have the right idea to start the juke when the chasing enemy is on a high ground ramp, but they can't time the highground fog jukes properly.

8. not good at prioritizing specific heroes in team fights (cores over supports, if both look equally chasable)

9. terrible at dealing with split pushes. They prioritize defending their towers over everything. Also bad at split pushing, in general.

10. bad at properly utilizing buybacks. If some heroes buyback during the defense, it is expected that the remaining heroes should ensure that the enemies can't escape, otherwise buybacks would be pretty useless.

11. when they are behind, they simply don't have any coherent way of catching up other than taking huge team fights. Which the enemy team will deny the AI, if they are smart.

For now winning lanes and having overwhelming team fighting abilities is the only meta that the AI seems to be doing.