How to enter and play a hidden test level?

[Aetherius]

Hi, I'm currently experimenting with the GC game Rocket Power Beach Bandits.  I've managed to extract all the game files, and I'm interested in finding a way to explore an unplayable test level with your in-game character.

I figured the most logical way to do so would be to edit the script or lines of code that bring you to the next level.  Let me explain.

Let's call the first area of the game level A, the second area level B, and the test area level C.  Instead of the end of level A bringing you to level B as per norm, the edited script/cfg/txt would load in level C instead of level B.  The problem is, the game was made by an obscure dev team that used (to my knowledge) file formats that were not popular in the GC era.  I would like to know:

1) Is my theory of editing a "script" possible to get me to level C, or is it much more complex than that?

2) If so, which file type would it be?  The file formats I extracted that could be this elusive "script" include the following: .dat, .bak, a single LOD.dll file, .bsc, .cb, .cfg, .chp, .db, .dbx, .ent, .mtap, .npbx, .spline, and .tpa.

I apologize if this is a vague question; I'm not sure how else to word it or go about asking since I'm not a CS expert.  Thanks in advance.

[JMC47]

The easiest way would be to extract the game's executable, find the level loading code in that, find it in memory when booting the game, and the modify memory with either a cheatcode or Dolphin's debugger to point to a different level.

This requires a lot of work, but it's probably the easiest way to do it. If you can't extract the executable and analyze it, you could also try and guess and check by comparing what the game is doing when loading different levels and try to find the routine for level loading manually.

[Aetherius]

The easiest way would be to extract the game's executable, find the level loading code in that, find it in memory when booting the game, and the modify memory with either a cheatcode or Dolphin's debugger to point to a different level.

This requires a lot of work, but it's probably the easiest way to do it.  If you can't extract the executable and analyze it, you could also try and guess and check by comparing what the game is doing when loading different levels and try to find the routine for level loading manually.

Thanks for the quick reply JMC.  The first problem with that however is that the .iso is comprised of some misc files and a single .pak which contains the entirety of the game.  I can extract the contents using QuickBMS, (which is where I can view the several file types in the OP) but attempting to recreate the iso with the extracted files instead of the singular pak leads to errors.  There's no executable to be found inside either, and since the game uses solely that pak file, analyzing it while it's running would be hell since it's technically just one file.  

To top it off as well, there is not a single AR or Gecko code listed for the game.

What can I do from here?

[DJBarry004]

The executable usually has the name "main.dol" or something like that.

On that same list, right-click where it says "Disc" and then "Exctact System Data".

Choose a folder where to extract those files and you will find it there.

[JosJuice]

The executable usually has the name "main.dol" or something like that.

Technically, the main executable doesn't have a name on the disc. Dolphin assigns it the name main.dol when you extract it since it has to have some kind of name when saved as a file.

[Aetherius]

Welp, seeing as I have zero experience with hex there's really not much I can do with this information. I opened the .dol with BrawlBox to view it but it's (literally) a different language to me and I have no clue where to even begin. Thanks for the help anyway though.