Almost 20 years later and people are still finding new things about old SuperNES RPGs.
Sort of confused, what was the big secret?? :O
gifs with sound time!!!!!!.
The extra rooms at the far end of the tunnel. Normally you have like four different doors to choose from with the last one being the one that leads you further into the dungeon but by standing on the right pressure plate for a minute or two you can access an additional set of rooms which includes getting the Light Shaman earlier than normal, a few extra chests, a few extra dummy fights, and a cell with some NPCs in it.
Apparently, the internet at large didn't know about this until about a month or two ago. Not game changing, but neat never the less (kinda like the Chicken Lady of LttP(1) that nobody really knew about until a few years ago).