Board Thread:Questions and Answers/@comment-24385143-20140111195955/@comment-24203473-20140112010139

Gold Island is a "special case" when it comes to where a monster is located; a monster exists on both the original island it came from AND Gold Island, at the same time.

For Ethereal Island and Shugabush Island, teleporting the monster is a one-way trip; once a monster leaves the original island it is from, it is permanently moved to it's new home. Currently, no monsters from Ethereal Island OR Shugabush Island can be placed on gold island.

Hope this helps!