The 19-pages Game Design Document describes the game Trash Hero. The document is based on a GDD template by Chris Taylor.
You can gasp the idea of a game in 1-minute video pitch above. The description of the game:
Trash Hero is an action platformer where you collect trash and fight mutated insects on the tropical beaches, in jungles and other natural environments. Between levels you are building a base: construct and upgrade facilities of a recycling plant where gathered trash is recycled into materials. Materials are used for building eco-village and crafting equipment, which provide new abilities.