Slime Forest Adventure is a learning RPG which aims to teach a basic set of Japanese language skills. The free demo version of the game teaches the user how to identify all hiragana and katakana characters, along with up to 200 kanji, and also contains supplementary grammar training. There are two premium versions of the game: Gradeschool Kanji expands the kanji covered to 1,000 and Common Use Kanji expands it to almost 2,000. Each also includes supplementary training modes.
Editor’s Note: the main site is a bit lacking, but for more information, check out a user-created wiki at http://slime-forest-adventure.wikia.com/wiki/Slime_Forest_Adventure_Wiki