You can make a custom map on minecraft with out a map editor by building or demolishing certain land features or you can use a seed by typing your seed in the bottom box on the "create new world" menu.
Try using a map editor, like MCEdit.
Try MCedit. See the link below.
There is lots of them.
The best place to look is on the minecraft forums
There isn't an Map Editor in Animal Crossing.
yes it will have a map editor but i am not sure if it is multiplayer
no
try using a map editor/ viewer
Yes, it shipped with a map editor standard. It will not edit the game, however.
Some might, but an adventure map is a MAP, not a mod. Just search for "adventure map" on Google or the Minecraft Forum.
there is no such thing as an ActionReplay for a map editor, you have to be pro to use one like a ROM and a map editor, but no-one has been able to edit the maps in Pokemon diamond yet because of their 3D values