Beat the 3 planets go to the crystal click on the key
On poptropica, when you get to the asteroid belt, if you are looking for Mordreds little castle that holds the key, go to: X 12 and Y 80. There you will find the little asteroid Mordred is hiding on.
walk in then yo are going to do a puzzle go to the link of this page
there no key for poptropica
Simple, all you have to do is shoot at them, and don't get hit. The building that's in the asteroid belt is in the middle, when you get on the planet touch the key. A funnel-like, black hole-looking warp thing will open up. Enter that and it will take you to where Mordred is.
On AstroKnights Island, the bales of hay hide the secret entrance to Mordred's laboratory. The key is in the secret chamber under the village fountain. Use the Cosmic Symbols diagram from the mill : press "moon, Saturn, star"and then the sun.
there is no key
You need to go to each planet and beat the creatures and then get the three knights. Then go to the place where you saw the key and you will see (the thing was that you needed those three knights). BTW - ONCE YOU PULL OUT THE KEY, IT WILL BRING YOU TO ANOTHER GALAXY!
first make sure you have gotten a key from under the fountain if you haven't press on the planets on the fountain and press the moon the planet that looks like Jupiter the star and then the sun go down and once your down there talk to the last guy on the right and he'll give you a key once he does go to where the town is
go to the asteroid feild and dodge rocks til you find metal island on rock then pull key out of stone
It depends on what key your talking about?
there is no key.
there is no hole because there is no key