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-   -   Pokemon Yellow: IVs, DVs AI team size, movesets, evolution method (

GamerXYZ 5th March 2014 01:42 AM

Pokemon Yellow: IVs, DVs AI team size, movesets, evolution method

I'm looking to change Pokemon Yellow a bit. Unfortunately, I'm not experienced with hacking games, and I couldn't find what I need. Does anyone know how to do the following things? Hacks, codes, save editor... anything's fine!

1. I'd like to give all AI trainers' Pokemon max IVs. I know almost all of them have very low values, which makes them weaker than they should be. Wild Pokemon don't matter. Is there a way to do this?

2. I'd like to permanently set the DVs (that's what EVs are called in Gen 1, right?) of my Pokemon at 0. Opponent can't have DVs, so neither should I. Is there a way to do this?

3. I'd like to set the team size of the rival at 6 for all his encounters (including his first: I'm planning on giving both of us a team of 6). The reason is: I know a program that can change the Pokemon he uses (would that also properly change moves?), but said program can't open new slots. Is there a way to do this?

4. I'd like to change the movesets of some Pokemon (levels that moves are learned, but also give some Pokemon like Exeggutor an actual moveset). Is there a way to do this?

5. Finally, I'd like to change the evolution method of some Pokemon (either a lower level, or an entirely different method like turning stone-evolving into level-evolving). Is there a way to do this?

Hopefully, I'm not asking the impossible: this would make the game alot more fun to play :)

Miksy91 5th March 2014 03:29 AM

All those things are more than doable, but we haven't researched yellow enough so that I could give straight pointers like "edit this here and this here" for the wanted effect to take place in the game.

When I myself plan on adding a new functionality or two, I usually use either debugger or try to track down the address, to write my new code in, with an assembly editor (when I know enough background information about what the "thing" is about).

Sorry, can't help you more than that with questions 1 and 2. But both of those things can be changed easily when you know enough about rom hacking. Until then, I'd say, you won't be able to do anything about them. (Especially question 2).

3, 4 and 5 can be done by knowing the basics of hex editing, pointers and tables. But yeah... some background information required here as well.

GamerXYZ 5th March 2014 06:39 PM

Thank you very much for the reply.

Seems I can better skip the idea then. Basically, as an idea for a casual playthrough, I was planning on giving myself the rival's E4 team (all 6, if you exclude the 3 starters), while giving the rival a team of all 3 Eeveelutions (or 3x Eevee, depending on how early the encounter is) + 3x starters. But for just a casual playthrough, that would be too much effort.

The problem is of course: some of the Pokemon learn moves ridiculously late (Rhyhorn has only Horn Attack until lvl 35, for instance), evolving by stones is not as smooth as by level (and Kadabra can't evolve at all), and the stone evo's (Exeggutor and Arcanine) learn no moves of their own (except for Stomp for Exeggutor). The rest is simple: the rival's team size would need to be expanded, and the IV and DV change is just to balance the game vs the AI.

I specifically picked Yellow because that IMO does the rival's team best (no Special split, no abilities, no Dark/Steel, different ways some attacks worked, etcetera) and thanks to Twitch Plays Pokemon (but Yellow instead of Red, because Yellow has some very likable changes).

Miksy91 5th March 2014 09:02 PM

Not sure what to tell you really apart from checking out tutorials for doing this and that..

This guide is very outdated and explains some things wrong. For example, I wouldn't be surprised at all if most addresses described for RBY would only match for Red and Blue and not Yellow!

Nevertheless, you can for example see that documentation behind evolutions and moveset learning data for RB(Y) is under section 12. As I said, those addresses should work for Red and Blue, but could be very different for Yellow. The datas should match though! What I mean by this is that pokemon evolve at the same levels and know the exact same moves in all three versions, don't they? Because of us knowing this, we can use that information for finding the data easily in Yellow.

You can use the "Search" function of any hex editor to look for data in bytecode. Just see what's written (as bytes) under one of those addresses (for instance, Kadabra's data to make it possible to evolve it to Alakazam in yellow) in a red or blue rom, and search for that exact same data in pokemon yellow, and you should be able to find what you're looking for.

This is a pretty good way to start practising hacking by the way! :) I also started out by doing a few evolution method edits here and there and eventually learned a lot, lot more.

GamerXYZ 6th March 2014 06:00 AM

I have 1 more question: decided to just go a simpler route, and I'm now playing Pokemon Crystal with a 6-starter party, edited with Pikasav. I made 100% certain I put in everything correctly (I have experience with save editors of newer gens).

It seemed to work right, but whenever I heal in a Poke Center, the names mess up, some worse than others. For some the OT messed up. Also, I tested the Pokemon whose name was messed up the worst, and he froze the game after he used Growl.

Is there any other save editor (or a different, relatively easy way)? Note: I found a save editor for No$GBA-specific saves, but I'm afraid that won't work for me, for I don't use No$GBA.

Miksy91 6th March 2014 01:27 PM

Sounds like Pikasav won't work at all because the addresses are very incorrect for editing save files of pokemon crystal (u) rom with it.

Depends on what you mean by "relatively easy way". All you would have to do is to hack the data currently being loaded to ram.

If you for example want to change the pokemon/their moves that are in your party, edit the stuff starting at ram address $DCD7 (stands for "Number of Pokemon in Party" like you can see in under that link). You can edit that data with VisualBoyAdvance's built in Memory Viewer.

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