after you have found the cosmic simbles you must then go to the staute and put in the simbles in order then find the key from the freckle face boy with the wierdos in purple robes will give you the key to his lair and it is under the hay!
just go to coordinates x=11 y=81
you run up to it and keep pushing. the wall will eventually crumble
to the right in spy island
The key unlocks mordreds secret lab. You can get there by seperating the two hay bales.
Mordreds secret hideout is between the two hay stacks, but first you have to get a key to go through.
in the upstairs of the museum.
you just go to the lair in the thing, Dude!
In the Mordred museum on the second floor.
catch the mouse
obtain the small key then go to the stacks of hay , jump on top of them in the middle use the key the door will be unlocked go down the hole ......... and you are in mordred's secret lab
On Astro Knights island in the game Poptropica, Mordred's Lair is hidden in the castle. Inside the castle library (located on the right side of the first floor) collect the books "The Life of Mordred: A Cautionary Tale" and "The Mystical Weapon of Arturus" and click on the section of the library specified on your library card. A stairway will appear, leading you to Mordred's Lair.
If you are referring to the keycard in Poptropica Counterfeit Island, you use it to unlock a door in the secret lair, which can be found in the countryside. It is locked so you have to find a key.