Thanks to Helder from the Forums at The GHSI, I finally got some working No-Clipping Codes for Secret of Mana. (There has been another "Walk Through Walls" code floating around at other Game Genie code sites for awhile, but I've never been able to get it to work. These ones do.)

While they don't work everywhere (for example, I couldn't use them to re-enter the burned down castle in Empire Northtown), they worked well enough for me to prove the door in the Empire Northtown's Coffee Shop/Resistance Headquarters is merely background decoration and cannot be entered.

So I activated the codes for all three characters to get us down to the lower floor in this room of the Resistance Headquarters. But we'll have to turn the codes off once we're down there because you cannot enter doors and other "hot-spots" that take you to different areas of the game so long as the codes are in effect.

So I deactivated the codes and try to walk through the door and guess what? It doesn't open. You'll just keep pushing up against it, but nothing happens. It's only decoration and doesn't do anything. I guess that only leaves us with the question of whether or not this door was intended to have a purpose, or if it was always just meant to drive us nuts. Curiously, even with the codes deactivated, I was able to walk onto the stairway to the left and leave the room. Now why would you be able to walk through the stairway from the left side, but not go the opposite way on it? Maybe it really was intended to be a secret area like the Merchant in Tasnica at one time, but was changed. Or maybe I'm just crazy, I dunno.

   

I also used the no-clipping code to explore the "restricted" areas of Empire Northtown, hoping to shed some light on the World Map Gold Fountain/Carousel/Racetrack mystery. Unfortunately, there was nothing there.

   

The town just loops around. I thought for years that maybe that blocked-off portion contained a doorway to a secret area with the mystery map object. I even deactivated the codes to see if I could find a "hot-spot" that would warp me there, but alas, that was just a pipe dream. It's good to finally have some of these theories that have bothered me for years laid to rest, though.

These codes can have some strage effects. Use it on Karon's Ferry and your characters will scroll away with the backgrounds and continue to loop around the screen for the entire duration of the trip. Useless and pointless, but it does make Karon's "Leaving so soon?" line seem really funny.