Here is a sample game that meets your requirements. It's a simple space game where you create planets, collect gas, increase planet size, and watch out for stars collapsing or forming.
In this game, you can click on the canvas to create planets. The planets will start with a small size and will collect gas over time, increasing their size. However, if a planet becomes too big and reaches the edge of the canvas, it will collapse and be removed from the game. Stars are represented by yellow circles, and they will appear in the center of the canvas. After a minute, the star will collapse into a red giant and form a black hole. To prevent this, you need to create more planets to collide with the star and form a new star.
Please note that this is a basic example and can be extended and customized further to make it more enjoyable and interactive.