MWorld

It's a mode with 3 new ores as well as tools for 2 of them and armor for one of them.
Here is more detail of what it contains:

                                                                             Games

Amber :
-Block
-Tools

Ruby  :
-Tools
-Block
-Armor

Green Diamond:
-Block

In the future

-New Dimension
-World update : Structures, biomes etc....
-Useful control in games
-Added useful crafts
-etc......