This is a work in progress title! Do not buy this game if you do not want to fund us!
This game is an open world sandbox game. Everything in this world is already changeable. The blocks are very small compared to other games of this genre. Instead of 1 block per cubic meter we have 64 blocks per cubic meter.

What is already implemented:

A C++ based game engine (we created our own engine)
Beta Multiplayer
Motion captured animations
Infinite Landscape
Create your own landscape via a heightmap and vegetation density map
A lot of different block types (see wiki)
Pregenerated landscape: You can start playing the game in seconds!
Special shapes: Cylinder, Ramp, Arch, ...
Torches, lamps, camp fires (with dynamic shadows)
Chests
Doors
Boat
Water simulation
Electric wires (LEDs, buttons, ...)
Growing of plants and trees
A bed
Weapons (stick, sword, pistole, machine gun, grenade launcher, shotgun, sniper rifle)
A lot of different monsters: bears, zombies, wolves, sheeps, red deer, spiders, monkeys
Dungeons: natural and man made.
Grids
Paintings
Signs
Different types of landscapes
Caves
Ruins
Fire simulation
Heat simulation
Crafting via recipes
Voxel renderer
Deferred Rendering System
HDR Renderer
High End Animation System
Bullet Physic Engine
In-Game Entity Editor
Day and night cycle
Sky rendering system (physically correct)
Master of materials (some blocks have submaterials)
And of course such things as loading and saving do work. You can also die in the game, there is an inventory. When you die you will drop your backpack.

What we are planning:

Better "far landscape" and faster update (we want to be abled to drive with a car in the game)
Cars and other vehicles
Automatic generated buildings and better ruins
Train / Minecart
Automatic generated cities and NPCs which live in a dynamic world
Automatic generated quests
Special multiplayer editor with which you can create maps!
Multiplayer modes: Capture the Flag, Conquest, Team Deathmatch
Better dungeons with monsters, chests and furniture

If you unsure just check out the demo!

StaudSoft's Synthetic World Beta screenshots