Code is rarely the biggest thing in these programs. You want textures that don't look stretched and pixelated at 4K? That's going to cost you.
Look in any game directory. There's probably a one big file--sometimes a few big ones--in there that you can rename to .zip and unpack it as one. It will dump all the textures/sound effects/etc. in the game, but have zero code. It will be something like 70-90% of the game's entire space.