Sphere Ability

is it possible to have the sphere ability on other models and still have the spheres rotate around the units head?

if so, what attachments should be used, etc.

The attachment points on the bloodmage are what rotate. The sphere ability by itself doesn't rotate.

Yeah, those attachment points are the sprite1-3 attachment points.

You can simulate them with triggers though, but that would be the only way.

Or you can add them to a model. If you have 3dsmax 5 its not hard.

Add them to the model?
Somehow I'd rather use triggers than reimporting a model for 200+kb of the map's size.

Of course, in the case you're importing the model anyways, CL's method is indeed the easiest way.

could anyone possibly show me an example of how to do this maybe?

A model with 3 rotating bones wouldnt take 200kb, ill gaurantee you that.
Also a trigger would be rather laggy, as you have to move 3 units every 0.04 or so for every unit/hero you use this for. If you want to use triggers, just move dummies with the ball model every few ms to a polar projected point, with the angle increasing/decreasing every tick.