Nuff's certificate an item obtained by searching the shelves in Fairy Nuff's grotto during Fairy Tale II - Cure a Queen. It needs to be in the player's inventory when they want to access the Fairy Queen's hideout using the Fairy ring code sequence AIR, DLR, DJQ, AJS. Players no longer require it once they begin Fairy Tale III - Orks Rift. If lost, it can be re-obtained by searching the wrecked shelves in Fairy Nuff's cottage.
By studying the certificate you can see the following message on the back.
The Cosmic Rune Altar tablet needed to decipher the message.