I loved this the first time I saw it but couldn't think of what to write about it. I've never seen a greyscale piece that's quite as rich and varied as this; you quite simply nailed the assignment Someone in the comments mentioned horses and riders kitted out for battle; I agree, although I'd rather think parade than battle: white and grey stallions, ribbons in their manes, prancing and cavorting -- lovely stuff!
There are a lot of greyscale fractals around.
After that, a fav is just icing on the cake. Thanks for that, as well.