I'm sure the answer should be obvious for anyone with experience working with the software, but as a rank amateur I'm in the dark. As I mentioned in my introductory post, I have a few pipe dreams concerning a handful of nes games and fulfilling those involves some figurative heavy lifting. Before any of that can take place, I need to know if its even possible to work with a rom without having the source code at hand. For one example, what I would like to do is add two extra sprites for each enemy in Earthbound zero/beginnings as a form of pseudo-animation--an attacking sprite and a wounded sprite to be displayed when its the enemy's turn and during the flashing section once they've taken damage. In order to organize and install these new images, how much of the game's code would I need to fully grasp? EBZ is relatively fortunate as a few tutorial pages exist on romhacking.net's wiki, but I am not sure if these would help matters very much: http://datacrystal.romhacking.net/wiki/EarthBound_Zero:ROM_map Again, any sort of advice or guidance is immensely appreciated!