You guys probably remember Wurm Online that was posted by Notch here 12 years ago - I am very proud to announce that standalone version of Wurm client and server just got released on Steam! 
It will work parallel to Wurm Online - WO is still subscription based, while WU is Buy To Play.
Wurm Unlimited can be modded (and - unlike Minecraft - it is non-obfuscated, so can be easily decompiled to code very similar to original), so I am excited to see what mods will be created for this game (especially knowing fact that a lot of current Wurm Online players are programmers and there was big interest in mods/tools even before the release).
Wurm Unlimited is available here
Short description from game Steam page:
[quote]Wurm Unlimited is your full standalone version of the fantasy sandbox world Wurm Online, the MMORPG where the players are in charge!
A pioneer in the ideas of player influence, crafting and adventure, it is now one of the most deep and feature packed sandbox experiences available.
Whether you enjoy building your home, conquering kingdoms or hunting dragons, Wurm will let you.
Explore the world and make your mark!
In Wurm Unlimited, players can explore an elaborate fantasy sandbox world in the predefined Creative or Adventure modes as well as set up their own game server and invite friends to live and experience the Wurm universe.
What can I do in Wurm Unlimited?
Host your own Virtual World! The Server Management GUI hels you change settings such as skillrate gains, action timers, creature count …
Explore huge, diverse landmasses with creatures and mysteries!
Modify the terrain; dig, raise, flatten and sculpt the land around you!
Craft and use thousands of unique items.
Wage war on other kingdoms, and lead yours to victory.
Discover and fight over religious artifacts on a PvP server.
Capture and breed animals from the environment.
Train 133 Skills, 10 Player Characteristics, and 3 Religion Characteristics.
Follow one of four unique deities and religions. Or attempt to become a Deity yourself and join the existing ones on the moon of Valrei!
Hunt creatures such as the unique red dragon, forest giant, kyklops, troll king and others!
Become a priest or champion of your religion and learn powerful spells and enchantments.
Choose one of five meditation paths and take advantage of special meditation abilities.
Earn as many of our 200+ skill and achievement titles as you have time for!
Mount various creatures, from horses and carts to unicorns, bears and even dragons!
Construct, crew or even captain six different ship types with other players, from small rowing boats to impressive caravels.
Build a variety of structures, from guard towers to stone houses to fences, bridges and statues.
Found your own settlement wherever you desire; own land, build a farm, a castle, or perhaps an entire village!
Pave roads to connect settlements and plant signs to improve local infrastructure.
Live off the land by creating fields to farm a variety of crops including potatoes, garlic, cotton, wheat, strawberries, pumpkins and more!
Cook nutrious food using a huge range of ingredients.
… and much more!
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