Anyone that s started up undertale for the first time will encounter a mysterious locked door early in the game s snowdin area.
Undertale locked door.
Nothing belongs to me.
To do that you have to save just before he judges you and then reload several times until he gives you the key.
That key will open the back door.
Sea tea reward.
If used during the fight against mettaton ex the following text displays.
First you have to get the key to sans room.
If the mystery key is used on the mysterious door it reads the following text.
The protagonist can sleep in this room for 200 g yielding a similar effect to resting at snowed inn.
Glyde can be encountered in this room before fighting papyrus.
Frisk do not let them in.
The mysterious door is an area found in snowdin forest south of the right side of the room with the icy x s and o s puzzle.
The door which bears the delta rune is surrounded by glowing mushrooms and floating particles.
Handing over any of the listed items rewards a response and in most cases an item.
You used the key the lock clicks.
However unlike the snowed inn the money is not returned to them.
Cinnamon bun reward.
In the nintendo switch version examining the door leading to mad mew mew in the dog shrine before it is unlocked yields a message saying that the door is locked by a mysterious seal as an ominous piano jingle is heard.
Nothing will open it not even the expensive mystery key item.
You used the mystery key.