I actually purchased this during the Steam Summer sale and just got around to installing it.
Alchemists Awakening is also written in java. It looks a lot like rising world in its land generation especially the mountains. There are of course big differences , the Land generator seems to create endless islands on a huge sea, Rising world seems to hide its voxel stepping with a huge world of grass to cover up the voxel stepping. Alchemists Awakening worlds do generate some buildings and monuments here and there but I do not think they are procedurally generated. One unique thing you can do in this world is create monsters out of trees and rocks and somewhat give them orders.
The world also has animals and other beings you can fight or you can play in a creative mode where everything is docile. Of course you can also build anything you want just like in rising world. The water in the game also looks great and you can see the fish jumping as you fly or swim over or under the water.