Changed battle flow (switch pkmn BEFORE battle starts)

[Ragntard]

Hi,
Just started making my own rom hack and most resources seem to be here for changing things within the game but I see very little info on how to find parts of the code connected to core mechanics.
Or if there's an IPS patch or similar for this please let me know! (for emerald)

What I'm trying to do is overhaul the main game with a more strategic style of game play.
Already found an EXP all patch I've added and I'm adjusting most pokemon in the game and the wild pokemon/ trainers to be at about the same level as the user.
Also adding some fun things like specific gym leader pokemon with cleaned up gen 1 sprites (say an onyx that's rock/ghost type with stronger stats for the first gym), random "boss" encounters on the routes (switching the 1% encounter rate pokemon to higher level alternatives that can take an entire party to take down).


What I basically want is a rom hack that almost forces the user to constantly change pokemon and to not just use a main pokemon to quickly win every match and turn the game into a grind, and so changing pokemons BEFORE a battle starts will be important as the enemy gets a free hit on you every time you switch out, and since you will be switching out a lot your party might get wiped just because of that, and again users will avoid using anything but the first pokemon in their party.

(Lots of people suggest just going into menus and switching in the party but this is time consuming, kills game play, and doesn't work with random encounters as you need to select the right type for the next battle and you don't know what it will be).

I think this would be possible if you simply added the same function that's now in between each battle (do you want to swtich pokemon?) to the "script" for the start of the battle, right after "trainer 111 sent out 111".
But I have no idea how to find the location of these things within the rom...

Awesome if someone out there has an idea on how to do this!

[Ragntard]

Some more of the "boss" sprites if anyone ever sees this and wants to use them