Now I've done praising the inker, I should mention I love the colours too. This many characters could have ended up being a jumbled bright mess, keeping it slightly sombre allows the detail to shine through without drowning out the overall message.
What I like about the composition of this piece is the slight skewing of the classic 'defeated heroes' cover with a villain standing amidst the body's of the fallen. Here it's more spaced out and naturalistic and gives a better representation of the aftermath of a superpowered battle. That and the poses not clearly showing everyone's face adds impact. It's a nice twist on a very common trope.