Posted: February 7th, 2006
Last Updated: February 16th, 2009
The only level editor is called GNGWin which was created by Mega-Dog and made for Windows. You can edit any level as well as the tiles. It does not support enemy/item editing yet. Version 0.5.1 was released March 23rd, 2004.
Download Here (.zip - 334 KB)
Zophar's Domain lists another editor which is for DOS; however, when downloading the file it seems to be for Goonies II instead of Ghosts 'N Goblins.