When you enter waterfall (After sparing/killing papyrus) you normally keep walking till you reach San's station (At the first save point in Waterfall) you keep going right, the secret is at this waterfall (The one with the rocks falling from it to be specific ) But since i was in genocide so there were no rocks, Anyway when you get into the water you go up then suddenly the water goes up and you enter a small room with 2 Mushroom lanterns but it's empty You hum along with her, and you can get past her.Originally posted by FlameGamerDS:There was this secret door/gate thing that i found by luck (While playing the genocide run) You come to a fork in the road after avoiding Undyne throwing spears at you and the seed bridges. Don’t get too excited, though, because Undertale wants to mess with you a bit before you finish the puzzle. Once you enter the code, which can be very frustrating! A hole opens, and you can see a treasure. Please make sure you press Neutral with the directional arrows, or it won’t work. Here is the pattern: Neutral, Up, Right, Neutral, Down, Neutral, Down, Right. This will make more sense in the Extended Walkthrough.
You find out the pattern you need to enter when you give a statue an umbrella.
The first time I played the game, I didn’t get what I was supposed to do. I wasn’t expecting to find something like this in Undertale. Indies With Great Accessibility Features.