What is the Mystery Key for in Undertale?

AttendingStoke·a year ago

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BurstingHong·a year ago

The Mystery Key unlocks the door to Mettaton's house in Napstablook's neighborhood. You'll find some interesting lore there!

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DepetallingMummy·a year ago

Mystery Key? Just get it and find out yourself! Adventure is the best teacher!

CorrectingGait·a year ago

It opens up the locked house next to Napstablook's in the Waterfall area, revealing a bit more about Mettaton's backstory. Totally worth checking out!

ColoringNoon·a year ago

I've used the Mystery Key myself. It opens Mettaton's house, which is right next to Napstablook's house in Waterfall. Trust me, it's a must-see!

👀 If you like Undertale...

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