shapeshifting/dissolving/melting figure effect

jayburn00

Hi, I am trying to create an effect where I have a character either dissolving into a dark mist, or melting into a black shimmering liquid. I have been able to get some of this effect simply by adding a flame/smoke prop, or adding clothing and then applying a texture similar to that, but not quite the way I want it. Basically, I want to make a scene where the character looks as if they are transforming into said mist or liquid (and the mist or liquid has begun to spread out), but upper body is still human in appearance. Any suggestions?