Border Rain

There's a great sense of kinetic intensity to this one thanks to the particle effects. One can easily imagine a storm of nearly invisible shrapnel scouring the earth with each fiery blast. Powerful explosions, and especially fireballs, can actually darken the world for a brief moment. You captured that here. As well, the ponies under the shield actually look like they're being forced into the ground by the force of impact, their coats rippling as if under the pressure of a powerful shock wave. Like skin in a wind tunnel. The out-of-focus background actually lends to the piece. At least I think so. It's one very personal slice of a larger scene, and that focus is a strong one. Deciding to make the other ponies appear only as silhouettes might appear lazy to some, but I'd say it paid off. Against a backdrop of war-fire on this scale, only silhouettes are appropriate.

I'm not as much of an expert on colors as I might wish, but it's easy to appreciate the subtle use of green inside the shield at bottom right. It gives the image just a little more life, a little more "pop."

I think you could have pushed the power of the explosion further by distorting the air around it, away and/or around from the shield, to show the pressure wave. In addition, the central character looks like they're being driven straight down by the force of impact, though the explosion is at an angle from them. A slightly more off-balance stance might have better communicated the struggle to stand firm. Either leaning into the blast or away from it. Just slightly. Their manes definitely would have benefited from being blown around. As is, those manes appear to have been overlooked.

All in all, a pleasure to look at and exciting to hypothesize about. Personally I find myself wondering just what the griffons are using on these ponies, and why only unicorns are present.