I made this Cloud generator in the Nodevember and and as the name suggests its only made with nodes. I deformed an cube to this cloud. You can change: the density, the scale, the noise, the seed, the sharpness and the destortion. It look very realistic and you can controll everything you like. There are no other file formats available because I used vector displacement and I displaced a cube, so in other file formats it looks like a cube.
I hope you Enjoy it!