I had a lot of limitations with Unity 2D Particle System. The most features of Unity’s Shuriken Particle System was’t available.
So I started to Rendering parts out with 3ds Max to combine them in Unity as Sprite Sheets with different emitters.
Some Rendering examples out of 3ds Max:
First I was using Pflow to create the right motion, and to have a control of the scaling over the lifetime.
My next step was to put the Blobmesher on the top of the particles to get the fluid dynamics.
And at last I create a one mesh out of the Particles with the Mesher Modifier from 3ds Max.
To manipulate the surface with Pusher and Turbosmooth modifiers.