I had a game dynamic idea quite a few years ago that reoccurred in my mind today. It’s quite simple, so I decided to recreate it in vanilla JS rendering to a 2D canvas. I even wrote it in ES5, compatible even with Internet Explorer (from version 9, I suppose, but only tested in IE11).
I played around a little with simple rendering tricks to add some effects — shadow positioning to create a sense of depth, and not clearing the canvas entirely each frame to create a cheap motion blur effect.
Click/tap anywhere within the inner square and try to let the growing circle get as big as possible while consuming the most dots of a single colour. As you achieve higher chains, the difficulty increases.
There is currently no end goal in this game, but you might find it mildly addictive and hypnotizing.