I was playing Sonic 2 today and I noticed something kind of weird. They're infact 2 different doors that are in the level, but only 1 is used. door on the right was planted using debug, door on the left is default. The one on the left is also used multiple times in Death Egg Zone, but this other door doesn't seem to appear in the game, although they function exactly the same as shown in this next picture Pointless, probably but it seems to be something none the less. I don't know, I just thought it was kind of weird.