D&D: Neverwinter is a free-to-play third-person action MMORPG set in the Forgotten Realms world. It is based on the 4th Edition of D&D rulesets, but can be played without any knowledge of it. The game is maintained and released by Perfect World Entertainment. It launched in 2013 and features regular content updates called "modules". These include new gameplay features, elements, dungeons and generally just more content to play around with. The game is available both on Steam, and Perfect World's own distribution platform, Arc.
In this game, you play as one of several D&D classes including Hunter Ranger, Control Wizard, Guardian Fighter and several others. Each class has its own distinct play style and abilities, and at level 30 you can choose one of two specializations for them. As you adventure and advance in levels and equipment, new areas, dungeons and quests become available on the way to level 60.
What makes this game unique among MMORPGs is that it features an editor, which players can use to create their own adventures using a wide arsenal of assets, maps, scripts, monsters and other elements available to them. Then they can publish these in the Foundry, from which the regular players can pick any published adventure they want to play. They gain XP, loot and money for completing these just like for regular quests, and at the end of an adventure they can give feedback to the author.