#633 TECHNIQUES: Dynamic wall explosion by Grant Davis
Check out this awesome explosion technique by Grant Davis! It's part of his Battle of Helms Deep MOC which you can view here: https://www.flickr.com/photos/93970753@N05/15984199698/in/photolist-qmtcFY-jJ8EVb-qvU83J
The effect he's created is truly stunning with the pieces of rocks suspended in the air mid-explosion, and although you can't see it, these are held by rods or other thin parts that don't show from the angle it's been photographed. Grant's also uses transparent orange parts which have been illuminated with a light from the back, making them appear to be glowing to simulate the explosion.