You could create a hemisphere (half a sphere) mesh in a modeller, with the origin at the 'apex'. Half a geosphere would be best. Model it so that 'bottom' is pointing down the positive Z axis.
Then, find the point where the weapon hits the shield and place a copy of the hemisphere there, and point it at the target. You can texture the hemisphere with a suitable animated texture, or something.
Then, find the point where the weapon hits the shield and place a copy of the hemisphere there, and point it at the target. You can texture the hemisphere with a suitable animated texture, or something.