Please recommend an emitter

I understand you can attach particle emitters to models with .mdl editing. Well this is what I wanna do: I've got a fast moving flying unit and it's rather hard to see. So I want to add a kinda grey trail behind it. Does anyone know of a good particle emitter to use for that effect? I want the trail to be straight and it would be better if it wasn't fluffy or anything like that.

Unless you're incredibly artistic, your best best is to go through the various wc3 models in WE, and find one that has an emitter similar to the one you envision. You can then mdl edit one copy the desired emitter to your model, at which time you can modify it to suit your needs. Good places to look are mostly models in the "buffs" "unit -missile" and "ability" categories.

PS - If you're truly looking for a solid grey trail, that sounds more like a ribbon emitter than a particle emitter.

Ah, ribbon emitter then. It's not like I know the difference (I've done skins and a slight .mdl edit but I don't know too much) :)

The problem with browsing through the spells is that I'd have use each buff art for a unit model then swing the unit around in the WE to see the real effect. So I was hoping someone has done this before.

In anycase, what about that yellow trail-like thing the blademaster has on his sword when he uses his attack,slam animation? Is that part of the model or is it some fancy effect?

That's part of the model, as are almsot all ribbon emitters. Luckily, adding a ribbon emitter is fairly easy. A ribbon consists of a material (at the top of the model) and an emitter (at the very bottom). Compared with particle emitters, ribbon emitters (called "ribbon emitters" in the mdl, mercifully) are much more straightforward, with few parameters. Your best bet is probably to reverse engineer one from another model (blademaster, paladin, searing arrow, etc), and just paste a modified version into your own model (altering relevent objectID's of course).