How to play is explained here [1]

By the way you can run the games locally. Just download all files.

For the forest game you would have a local directory:

   ├── Build
   │   ├── Build_7_30_F.asm.code.unityweb
   │   ├── Build_7_30_F.asm.framework.unityweb
   │   ├── Build_7_30_F.asm.memory.unityweb
   │   ├── Build_7_30_F.data.unityweb
   │   ├── Build_7_30_F.json
   │   └── UnityLoader.js
   └── index.html

then just run the following in the directory

    python3 -m http.server

[1] https://www.youtube.com/watch?v=a74KM792gbo