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Comment by kenhwang | Hacker News Reader

Going to echo what I said last time before everyone falls for the propaganda. The bots did not play at a top tier level, the bots didn't even play at a level that could be considered median level. They did not discover new mechanics. They couldn't even understand basic mechanics. Their coordination was no more sophisticated than "wander around together and press all the buttons on the first enemy".

They were showing some signs of competitiveness because of their consistently better than human mechanical skills. You can go a long way in Dota2 off solid mechanical skills.

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> They couldn't even understand basic mechanics.

Can you expand on this?

Off the top of my head:

- using skills against targets where the skill would have no effect

- using skills on nothing with all plausible targets not remotely nearby

- using items to turn invisible and then immediately taking an action to remove invisibility

- everything regarding vision/detection: placing vision where vision already exists via structures, placing multiple sources of vision on top of each other, buying detection items when none of the opponents could turn invisible, placing detection in areas where detection already exists

- using a item that's canceled by close proximity to enemies in obvious close proximity of the enemy

- waiting for a neutral respawn when its impossible for it to respawn

- stacking effects that don't stack

Then there's obvious poor utilization of skills, such as:

- using a skill that does more damage for every point of missing health on targets that have no missing health

- using ults with long cooldowns on neutrals when that hero's normal skill does more damage with much much lower cooldown

- using skills that multiply it's effectiveness when there are secondary targets when there's obviously no secondary target near the primary target

- casting damage amplification on a target (target takes more damage) and then not dealing damage

You're missing the forest for the trees. Yes, it is true that the bots was suboptimal and made elementary errors, notably around vision. However, overall they did really well. The mere fact that they could coordinate with each other without explicit communication was very impressive.

On each of the poor utilization of skills, I could counter by saying there were other objectives in play. For example, you didn't mention that the "skill that does more damage for every point of missing health on targets" also happens to freeze the target for 1.5 seconds. Perhaps the goal of the bot was just to hold the enemy in place.

Honestly it's pretty easy to sit around saying "yeah nothing impressive here". But I've been playing this game for a decade and fact is, if I had seen OpenAI 5 a year ago I simply would not have believed it was possible for bots to play this well.

> n each of the poor utilization of skills, I could counter by saying there were other objectives in play. For example, you didn't mention that the "skill that does more damage for every point of missing health on targets" also happens to freeze the target for 1.5 seconds. Perhaps the goal of the bot was just to hold the enemy in place.

Using scythe to hold a Bkb'd target in place is a classic use of an immunity piercing stun acknowledging you'll get zero damage. This wasn't the case in the game I watched them play, it was just "a stun". Which is fine, honestly. But they prioritised the stun over the damage and the respawn time increase (which is actually just as important as the damage). I'm not sure I believe they understood all of the aspects of the spell based on how they used it.

The reality remains that the bots are just playing micro level incredible dota, and macro level mediocre dota. There are endless examples. Giving aegis to supports, never stacking creeps for carries, ganking low importance heros, using DP ult to farm jungle.

They're still better than me and probably anyone I'll ever play with. vOv

Sure, it stuns, but it was often stacked with other stuns. I don't remember it ever being used on a low health target. So I'm drawing the conclusion that the bot only understands that the skill stuns, but doesn't understand the scaling damage.

It's impressive that the AI managed to gain a rudimentary understanding of the game almost completely independently since DotA2 is a very complicated game. It's just not interesting problem because game mechanics can easily be codified. It's like being impressed at self-driving cars because the AI learned that it should stop at a red light, it should just be coded to stop at a red light. Learning to stop at a red light isn't the interesting problem that needs solving for self-driving cars.

It's definitely not the "AI is better than humans" narrative that these articles like to push.

They do in fact broadcast information to teammates [1] in recent versions:

> OpenAI Five sends 512 such values every couple of milliseconds

I think one of the challenges to making the bots play realistic Dota would be to limit this passage of information. I would say only one bot can talk every time period (say 1.5 seconds) and minimum time before new information is broadcast is >0.5 seconds.

[1] https://medium.com/@stelmaszczykadam/do-openai-five-dota-2-b...

I think that smart teams are going to extract what they can out of these bots. Even top players had difficulties dealing with the inhumanness of the bots - people are generally trained to compete against something that acts to some degree on instinct, not probability.

The bots lack if fear in e.g. diving a tower before 5 minutes definitely paid off to a certain degree.

I also personally feel that the caster stack of players intentionally lost their matches to hype OpenAI. The limitations of the bots were very apparent, and the pro players at TI easily outsmarted the bots by either:

- Split pushing with 1 hero and fighting with 4.

- Baiting a lower priority hero (e.g. Lion). The AI would very often vastly overcommit for kills in the lategame.

Not even lategame, they overcommitted at all points in the game. Those tower dives for trades early game rarely lead to an objective or advantage. They were able to trade early because superior mechanical advantage matters more early game.

By the time midgame rolled around, it was pretty clear how naive their strategy was. It has an element of surprise to it since it's not a very human strategy, but just because it's not human doesn't make it remotely good.

It's like watching a a car drive on a sidewalk in reverse uphill and honking to avoid pedestrians. It's very impressive that the car figured out that driving on sidewalks reduces collisions with other vehicles, and honking reduces the chance of hitting pedestrians, and it's doing that all while driving in reverse which is very hard for a human to do. But no one in their right mind would call that good driving.

That's a great example. It would be great if you could write a blog post on OpenAI Five. There's a LOT of misinformation on this and could use a treatment like this: https://www.alexirpan.com/2018/02/14/rl-hard.html

> The bots lack if fear in e.g. diving a tower before 5 minutes definitely paid off to a certain degree.

It paid off because the bots were familiar with the 5-courier format, and knew that they could ferry in consumables to recover quickly. This is not normal in DotA 2; the game was balanced around consumables being limited in the early game, and the human players OpenAI faced were not familiar with this new, unbalanced state of affairs.

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