fantasy.grn.dk is コトバモン KotobaMon — a 3D monster-catching game that runs in an ordinary browser tab, where every monster is a Japanese word. ヒバナ hibana is a spark, コダマ kodama is a tree spirit, and catching one is how the word gets learned. It has a procedurally generated island with five biomes, twelve species, turn-based battles with a type chart, and full Japanese voice-over subtitled in Japanese, romaji and English at the same time. There is no download, no account, no build step and no backend: the whole game is 2,821 lines of vanilla JavaScript plus a vendored copy of Three.js, served as static files.
abc.grn.dk teaches a child to write an alphabet rather than to recognise one: pick a letter, trace it with a finger, and the app scores the shape you actually drew and tells you how close you got. Thai first — all 44 consonants, free — with Japanese hiragana and katakana behind a premium gate. Everything happens in the browser: the handwriting recogniser is plain Dart running on the device, the spoken letter names are files bundled with the app, and there is no account, no runtime backend and no advertising.
A look at fantasy.grn.dk, a browser-based 3D game that teaches Japanese with no build step, procedural art and self-hosted AI voice, and what its constraints show about shipping interactive products fast and cheap.
