Attached Link: http://www.renderosity.com/messages.ez?Form.ShowMessage=2297387

Muzzle flashes and explosions can be done to some extent in Poser. In the attached annimation there is a square prop with texture and transparency map inside the "bomb", in frame 2 the bomb is moved under the ground, the square is scaled up throuout the animation and moved slightly closer to the camera. The linked thread posts #3 and #4 demonstrate a muzzle flash and fire ball. These were all done in Poser 4, they are a bit primitive, later versions of Poser may be capable of better effects, I don't know.