Sure, here's an example of a simple 3D game about a young wizard on a quest to defeat a powerful dragon. It uses HTML, JavaScript, and ASCII art for simplicity. Note that this example doesn't include actual 3D graphics, but provides a basic structure for a game.
To play the game, you can open the HTML file in a web browser, and it will display the game prompts and choices. The example assumes a smartphone operation, but it can be played on any device with a web browser.