I'd like to get started on ROM hacking, and I would like one of my first hacks to be porting a mechanic from Sonic 2 Beta into Sonic 2 (final). The mechanic I would like to use is the one where Sonic rebounds off a wall. I would like to use this mechanic to not only make a challenge for others, but for me as well. May I get some tips on what I assembly code I should port over from the beta to the final? Thanks! P.S. Could I also get some tips on how I could add my own sprites without using any weird third-party tools? Thanks again!