In the first iteration, I imagined a universe with spiral galaxies that keeps colliding and exploding with spawners.

For the second iteration I tried to recreate the effect of a snowing globe.

I got my concept settled in the final iteration. This world is a multiverse of four parallel dimensions in fish tanks. Pollutants keeps spawn from the earth in the form of dark liquid. As the pollution level increases, light and living species will disappear from the world.