Idea's for modeling a fallen thousand son

[Reede]

Hey all, so I'm in the process of modeling my Wolf Lord and I've started to think about what I want to do for his base. Here's my general idea. He's posed with the legionnaires running legs from Kromlech. I was thinking of him stepping on top of the body of a Thousand Son that is crashing into the ice they're standing on with a giant gash in his torso (from the Jarl's axe) with dust escaping from the body.
 
I plan to model the thousand son similar to the model on the forgeworld Angon diorama that's being thrown backwards from his axe which is probably gonna take a bit of green stuffing work to pose the armies and legs correctly.
 
As for the dust escaping from the body I was wondering if you guys have any ideas. My first thought was to model a sort of fireball coming out of him and cover it in a layer of very fine course grey sand, but to be honest I want to go a little bit bigger and give it a sort of spirit look of humanoid shade escaping from the armour. However this is something I don't think I'd be likely to pull of green stuffing (hell my entire lack of experience has me scared of just the model reposing involved in the first part). So does anyone know of any good tutorials or, even better, some good models that might cover this. I came across this model that I thought might cover it, but it's a bit much, and I was thinking something a bit more vague humanoid shape, not cloth clad ghost.

 

Update: Another idea has come to me. If I take a featureless bald head, two arms (such as from the ghouls) and stick them together via a bit of sprue. Then green stuff down what would basically be a cape that is a down-facing triangle, and try and add some form to it to make a ghostly looking thing. Anyone know any good heads that would fit this?

 
Here's an image of the type of ice base i'll be doing and the Jarl who is currently based *and not fully glues together for painting reasons
http://farm4.staticflickr.com/3834/9360411571_cb98cd9445_n.jpg
http://farm8.staticflickr.com/7423/12192204524_029c2d7b10_n.jpg