One of the biggest additions to the realm is the Sky dimension. It was originally planned to be put in the game but got scrapped in place of The End. The fun part is how you get there. All you need is a bed and, as if it were a dream, you will randomly be transported there upon sleeping. You are then brought to a small house in the Sky Dimension. You can either fall back down to your own bed or search for the Pigman Village to find the Dream Pillow, which will allow you to travel back and forth whenever you want.
One note of wary though is that the world is protected by Giants and the Red Dragon so explore at your own risk.
The Ruby Ore has now been added, which can be used to trade with the Pigmen in the Sky Dimension. It will help you gain their trust to get the Dream Pillow but it serves little other purpose in its present state. And along with the Sky Dimension a never used Cherry Tree that only grows there lends for a new pinkish wood block to be crafted.
There are many other neat new, albeit old, additions that come with this mod. While most of these have probably been scrapped for good, some may be added in later versions of the official game but until that happens, this mod seems to be your best bet for playing around with fun items that you may have never seen before.