Lands of Languages (link) is an RPG for learning language vocabulary. In LoL you explore a procedurally generated world inhabited by wild beings. These can be captured and trained in battles involving translation challenges. There are verified translation challenges currently in English, Danish, Chinese, and a few in Vietnamese and German.

In addition to the game, a 69 minute soundtrack (link) has also been made public. This is licensed under Creative Commons and has melodies for different types of RPG environments.

A trailer for the game has also been made public here. Finally, here is also an image illustrating an environment in the game world.