[HN Gopher] Gemini 3 Pro vs. 2.5 Pro in Pokemon Crystal
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       Gemini 3 Pro vs. 2.5 Pro in Pokemon Crystal
        
       Author : alphabetting
       Score  : 238 points
       Date   : 2025-12-16 12:48 UTC (4 days ago)
        
 (HTM) web link (blog.jcz.dev)
 (TXT) w3m dump (blog.jcz.dev)
        
       | jwrallie wrote:
       | Being through the game recently, I am not surprised Goldenrod
       | Underground was a challenge, it is very confusing and even though
       | I solved it through trial and error, I still don't know what I
       | did. Olivine Lighthouse is the real surprise, as it felt quite
       | obvious to me.
        
       | wild_pointer wrote:
       | I wonder how much of it is due to the model being familiar with
       | the game or parts of it, be it due to training of the game
       | itself, or reading/watching walkthroughs online.
        
         | andrepd wrote:
         | There was a well-publicised "Claude plays Pokemon" stream where
         | Claude failed to complete Pokemon Blue in spectacular fashion,
         | despite weeks of trying. I think only a very gullible person
         | would assume that future LLMs didn't specifically bake this
         | into their training, as they do for popular benchmarks or for
         | penguins riding a bike.
        
           | criley2 wrote:
           | While it is true that model makers are increasingly trying to
           | game benchmarks, it's also true that benchmark-chasing is
           | lowering model quality. GPT 5, 5.1 and 5.2 have been nearly
           | universally panned by almost every class of user, despite
           | being a benchmark monster. In fact, the more OpenAI tries to
           | benchmark-max, the worse their models seem to get.
        
             | astrange wrote:
             | Hm? 5.1 Thinking is much better than 4o or o3. Just don't
             | use the instant model.
        
           | ctoth wrote:
           | > as they do for popular benchmarks or for penguins riding a
           | bike.
           | 
           | Citation?
        
           | dwaltrip wrote:
           | If they game the pelican benchmark, it'd be pretty obvious.
           | 
           | Just try other random, non-realistic things like "a giraffe
           | walking a tightrope", "a car sitting at a cafe eating a
           | pizza", etc.
           | 
           | If the results are dramatically different, then they gamed
           | it. If they are similar in quality, then they probably
           | didn't.
        
       | oceansky wrote:
       | "Crucially, it tells the agent not to rely on its internal
       | training data (which might be hallucinated or refer to a
       | different version of the game) but to ground its knowledge in
       | what it observes. "
       | 
       | Does this even have any effect?
        
         | blibble wrote:
         | I very much doubt it
        
         | tootyskooty wrote:
         | I'm wondering about this too. Would be nice to see an ablation
         | here, or at least see some analysis on the reasoning traces.
         | 
         | It definitely doesn't wipe its internal knowledge of Crystal
         | clean (that's not how LLMs work). My guess is that it slightly
         | encourages the model to explore more and second-guess it's
         | likely very-strong Crystal game knowledge but that's about it.
        
           | Workaccount2 wrote:
           | The model probably recognizes the need for a grassroots
           | effort to solve the problem, to "show it's work".
        
         | ragibson wrote:
         | Yes, at least to some extent. The author mentions that the base
         | model knows the answer to the switch puzzle but does not
         | execute it properly here.
         | 
         | "It is worth noting that the instruction to "ignore internal
         | knowledge" played a role here. In cases like the shutters
         | puzzle, the model did seem to suppress its training data. I
         | verified this by chatting with the model separately on AI
         | Studio; when asked directly multiple times, it gave the correct
         | solution significantly more often than not. This suggests that
         | the system prompt can indeed mask pre-trained knowledge to
         | facilitate genuine discovery."
        
           | hypron wrote:
           | My issue with this is that the LLM could just be roleplaying
           | that it doesn't know.
        
             | brianwawok wrote:
             | To test would just need to edit the rom and switch around
             | the solution. Not sure how complicated that is, likely
             | depends on the rom system.
        
               | Workaccount2 wrote:
               | I don't know why people still get wrapped around the axle
               | of "training data".
               | 
               | Basically every benchmark worth it's salt uses bespoke
               | problems purposely tuned to force the models to reason
               | and generalize. It's the whole point of ARC-AGI tests.
               | 
               | Unsurprisingly Gemini 3 pro performs way better on ARC-
               | AGI than 2.5 pro, and unsurprisingly it did much better
               | in pokemon.
               | 
               | The benchmarks, by design, indicate you can mix up the
               | switch puzzle pattern and it will still solve it.
        
             | jdiff wrote:
             | Of course it is. It's not capable of actually forgetting or
             | suppressing its training data. It's just double checking
             | rather than assuming because of the prompt. Roleplaying is
             | exactly what it's doing. At any point, it may stop doing
             | that and spit out an answer solely based on training data.
             | 
             | It's a big part of why search overview summaries are so
             | awful. Many times the answers are not grounded in the
             | material.
        
               | wavemode wrote:
               | It may actually have the opposite effect - the
               | instruction to not use prior knowledge may have been what
               | caused Gemini 3 to assume incorrect details about how
               | certain puzzles worked and get itself stuck for hours. It
               | knew the right answer (from some game walkthrough in its
               | training data), but intentionally went in a different
               | direction in order to pretend that it didn't know. So,
               | paradoxically, the results of the test end up worse than
               | if the model truly didn't know.
        
         | baby wrote:
         | Do we have examples of this in promps in other contexts?
        
         | mkoubaa wrote:
         | It might get things wrong on purpose, but deep down it knows
         | what it's doing
        
         | astrange wrote:
         | If they trained the model to respond to that, then it can
         | respond to that, otherwise it can't necessarily.
        
           | oceansky wrote:
           | I think you got a point here. These companies are injecting a
           | lot of datasets every day into it.
        
         | raincole wrote:
         | It will definitely have some effect. Why won't it? Even adding
         | noise into prompts (like saying you will be rewarded $1000 for
         | each correct answer) has some effect.
         | 
         | Whether the 'effect' something implied by the prompt, or even
         | something we can understand, is a totally different question.
        
         | elif wrote:
         | I would imagine that prompting anything like this will have an
         | excessively ironic effect like convincing it to suppress
         | patterns which it would consider to be pre-knowledge.
         | 
         | If you looked inside they would be spinning on something like
         | "oh I know this is the tile to walk on, but I have to only rely
         | on what I observe! I will do another task instead to satisfy my
         | conditions and not reveal that I have pre-knowledge.
         | 
         | LLMs are literal douche genies. The less you say, generally,
         | the better
        
       | soulofmischief wrote:
       | Nice writeup! I need to start blogging about my antics. I rigged
       | up several cutting edge small local models to an emulator all in-
       | browser and unsuccessfully tried to get them to play different
       | Pokemon games. They just weren't as sharp as the frontier models.
       | 
       | This was a good while back but I'm sure a lot of people might
       | find the process and code interesting even if it didn't succeed.
       | Might resurrect that project.
        
         | giancarlostoro wrote:
         | I have to think they need to know enough of the guides for the
         | game for it to work out, how do they know whats on screen?
        
           | soulofmischief wrote:
           | In my project I rigged up an in-browser emulator and directly
           | fed captured images of the screen to local multimodal models.
           | 
           | So it just looks right at what's going on, writes a
           | description for refinement, and uses all of that to create
           | and manage goals, write to a scratchpad and submit input.
           | It's minimal scaffolding because I wanted to see what these
           | raw models are capable of. Kind of a benchmark.
        
             | giancarlostoro wrote:
             | I have a feeling if you gave them access to GameFAQ guides
             | they might be able to play better, but it depends on how
             | you can feed them the data.
        
               | soulofmischief wrote:
               | It turns out that cutting edge super small (3b param etc)
               | models that fit in the browser are not great at playing
               | Pokemon on an even basic level, even navigation is
               | difficult when only providing raw visual information, and
               | object recognition of the low-resolution sprites is not
               | great. So I lost interest before even getting to the
               | point of providing specific strategy.
               | 
               | But, it runs in browser and works with any supplied ROM,
               | none of it is Pokemon-specific so I should set aside time
               | to serve it and make the code available
        
       | bbondo wrote:
       | 1.88 billion tokens * $12 / 1M tokens (output) suggests a total
       | cost of $22,560 to solve the game with Gemini 3 Pro?
        
         | brianwawok wrote:
         | True though I bet the $200 a month plan could do it, maybe a
         | few extra days of downtime when quota was maxed
        
           | AstroBen wrote:
           | For how long would it stay $200 of you can rack up 5 figures
           | if usage..
        
             | manmal wrote:
             | That is the reason they severely limited Claude Max
             | subscriptions. Some users racked up 1k+ in API equivalent
             | cost per day.
        
         | mkoubaa wrote:
         | I can't believe how massively underpaid I was when I was 11
        
           | re-thc wrote:
           | Do you hallucinate as a kid?
        
             | foundddit wrote:
             | At that age, it's called "imagination"
        
             | nomel wrote:
             | Kids definitely do this. They fill in blanks/context with
             | assumptions, resulting in all sorts of silly responses, for
             | topics of sparse knowledge/certainty. They're not lying,
             | because they think it's true. Sometimes the gap filling is
             | wrong, but usually downright brilliant, within the context
             | of their knowledge.
        
             | mkoubaa wrote:
             | All kids confidently state incorrect things it's part of
             | growing up
        
               | mikojan wrote:
               | That is just part of being a frontend developer
        
             | anal_reactor wrote:
             | My friend's son says he sometimes closes his eyes, imagines
             | cartoons, and watches them.
        
         | elephanlemon wrote:
         | "Gemini 3 Pro was often overloaded, which produced long spans
         | of downtime that 2.5 Pro experienced much less often"
         | 
         | I was unclear if this meant that the API was overloaded or if
         | he was on a subscription plan and had hit his limit for the
         | moment. Although I think that the Gemini plans just use weekly
         | limits, so I guess it must be API.
        
         | ogogmad wrote:
         | :/ Damn. That needs to cost 1000x less before people can try it
         | on their own games.
        
           | someperson wrote:
           | That's an extrapolation to finish the entire game.
           | 
           | If limit your token count to a fraction of 2 billion tokens,
           | you can try it on your own game, and of course have it
           | complete a shorter fraction of the game.
        
         | addaon wrote:
         | To beat it, not to solve it. Solving means something very
         | specific in the context of games -- deriving and proving a GTO
         | strategy.
        
       | squimmy26 wrote:
       | How certain can we be that these improvements aren't just a
       | result of Gemini 3 Pro pre-training on endless internet writeups
       | of where 2.5 has struggled (and almost certainly what a human
       | would have done instead)?
       | 
       | In other words, how much of this improvement is true
       | generalization vs memorization?
        
         | zurfer wrote:
         | You're too kind. Even the CEO of Google retweeted how well
         | Gemini 2.5 did on Pokemon. There is a high chance that now it's
         | explicitly part of the training regime. We kind of need a
         | different kind of game to know how well it generalizes.
        
           | kqr wrote:
           | I have a draft doing this with text adventures:
           | https://entropicthoughts.com/updated-llm-benchmark
        
         | prmoustache wrote:
         | Isn't that the point of a new model anyway?
        
       | cg5280 wrote:
       | I like the inclusion of the graph at the end to compare progress.
       | It would be cool to compare this directly to competing models
       | (Claude, GPT, etc).
        
         | kqr wrote:
         | It would unfortunately also need several runs of each to be
         | reliable. There's nothing in TFA to indicate the results shown
         | aren't to a large degree affected by random chance!
         | 
         | (I do think from personal benchmarks that Gemini 3 is better
         | for the reasons stated by the author, but a single run from
         | each is not strong evidence.)
        
           | casey2 wrote:
           | TFA says multiple times that the results are affect by random
           | chance
        
             | kqr wrote:
             | Yes, but recognising that is only the first step.
             | Quantifying the variance is the next step which I miss in
             | the article.
        
       | sussmannbaka wrote:
       | So after years of being gleefully told that AI will replace all
       | jobs an omniscient state of the art model, with heavy assistance,
       | takes more than two weeks and thousands of dollars in tokens to
       | do what child me did in a few days? Huh.
        
         | murukesh_s wrote:
         | I used to think the same until latest agents started adding
         | perfectly fine features to a large existing react app with just
         | basic input (in English) . Most of the jobs require levels of
         | intelligence below that. It's just a matter of time before
         | agents get to that.
        
           | blauditore wrote:
           | It's about the complexity of the task. Front end apps tend do
           | be much less complex and boilerplate-y than backends, hence
           | AI tends to work better.
        
             | etse wrote:
             | Isn't frontend more complex? If my task starts with a Figma
             | UI design, how well does a code agent do at generating
             | working code that looks right, and iterate on it (presuming
             | some browser MCP)? Some automated tests seem enough for an
             | genetic loop on backend.
        
               | murukesh_s wrote:
               | >Isn't frontend more complex? If my task starts with a
               | Figma UI design, how well does a code agent do at
               | generating working code that looks right, and iterate on
               | it (presuming some browser MCP)? Some automated tests
               | seem enough for an genetic loop on backend.
               | 
               | Haven't tried a Figma design, but i built an internal
               | tool entirely via instructions to agent. The kind of work
               | I could easily quote 3 weeks previously.
        
             | murukesh_s wrote:
             | I disagree - having worked on backends most of the time, I
             | find modern frontend much more complex (and difficult to
             | test) than pure backend. When I say modern frontend - its
             | mostly React, state management like Redux, Zustand, Router
             | framework like React Router, a CSS framework like Tailwind
             | and component framework like Shadcn. Not to mention
             | different versions of React, different ways of managing
             | state, animation/transitions etc. And on top of that the
             | ever increasing complex quirks in the codebase still needed
             | to be compatible with all the modern browsers and device
             | sizes/orientation out there.
        
               | rafaelmn wrote:
               | That's just a farmiliarity thing. I've worked on project
               | doing full web FE, mobile and BE.
               | 
               | It's hard to generalize but modern frontend is very good
               | at isolating you from dealing with complex state machine
               | states and you're dealing with single user/limited
               | concurrency. It's usually easy to find all
               | references/usecases for something.
               | 
               | Most modern backend is building consistent distributed
               | state machines, you need to cover all the edge cases,
               | deal with concurrency, different clients/contracts etc. I
               | would say getting BE right (beyond simple CRUD) is going
               | to be hard for LLM simply because the context is usually
               | wider and hard to compress/isolate.
        
             | ribosometronome wrote:
             | Or perhaps the sort of things it's been trained on? There's
             | not really a huge corpus of material re: beating Pokemon in
             | the manner it has to play Pokemon, especially compared to
             | the mountains of code these models have access to.
        
         | rybosome wrote:
         | "And, because AI never got any better or any cheaper after that
         | point, sussmanbaka's wry observation remained true in
         | perpetuity, forever."
         | 
         | - History, most likely
        
           | mchusma wrote:
           | Cost per intelligence is shrinking by something like 100x per
           | year. Even the Gemini flash release would potentially do as
           | well for 1/5th already.
        
         | dwaltrip wrote:
         | Children are incredibly smart. All of this was fantasy 15 years
         | ago. Comments like yours are amazing to me...
        
       | elif wrote:
       | Give it the gameFAQ next time
        
       | orbital-decay wrote:
       | The baked-in assumptions observation is basically the opposite of
       | the impression I get after watching Gemini 3's CoT. With the
       | maximum reasoning effort it's able to break out of the wrong
       | route by rethinking the strategy. For example I gave it an onion
       | address without the .onion part, and told it to figure out what
       | this string means. All reasoning models including Gemini 2.5 and
       | 3 assume it's a puzzle or a cipher (because they're trained on
       | those) and start endlessly applying different algorithms to no
       | avail. Gemini 3 Pro is the only model that can break the initial
       | assumption after running out of ideas ("Wait, the user said it's
       | just a string, what if it's NOT obfuscated"), and correctly
       | identify the string as an onion address. My guess is they trained
       | it on simulations to enforce the anti-jailbreaking commands
       | injected by the Model Armor, as its CoT is incredibly paranoid at
       | times. I could be wrong, of course.
        
         | jug wrote:
         | I've had some weird "thinking outside the box" behavior like
         | this. I once asked 3 Pro what Ozzy Osbourne is up to. The CoT
         | was a journey, I can tell you! It's not in its training data
         | that he actually passed away. It did know he was planning a
         | tour though. It had a real struggle trying to consolidate
         | "suspicious search results" and even questioned whether it was
         | fake news, or running against a simulation!, determining it
         | wasn't going to fall for my "test".
         | 
         | It did ultimately decide Ozzy was alive. I pushed back on that,
         | and it instantly corrected itself and partially blamed my query
         | "what is he up to" for being formulated as if he was alive.
        
       | reilly3000 wrote:
       | I'd love to see how the new flash-3 model would fare.
        
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