only thing I can think of is to create a model, like a sphere, made out of many many tiny spheres. Group it all together and texture it with whatever texture looks good for the fireworks, then use the explode objects button in the edit toolbar and move em apart bit by bit for every frame. It ain't the best way, I'm sure, just the only thing I can think of at the moment to animate it. Thoght that wouldn't be on a 2D plane, but you might be able to use a path to keep it on the 2d plane or to control the direction. Hawk would have to tell you more about paths than I can

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