The thorns are the work of Malificent, from Sleeping Beauty. I don't think it has any ties to any other worlds.
finally someone with a bit of knowledge. :wink:
If you don't recall the room where the cornerstone of light is held, became shrouded in thorns due to Maleficent exploiting the door which appeared in Pete's past to gain access to the area, however her attempts were foiled at the hands of Sora & company.