It's bugging me that Avacyn's wings and spear blade look... unfinished. The darkened area around her eyes also seems too large. Though, I realize, given the source of the light, her eyes would likely appear as they are now.
I do love the dynamic pose and overall composition. I could just imagine her descending from the sky to rescue a band of cathars or villagers; prepared to strike down their fiendish harassers.
In all seriousness, I love this card, and I love your interpretation of the character. Your rendition of Avacyn is most intense.
I do love the dynamic pose and overall composition. I could just imagine her descending from the sky to rescue a band of cathars or villagers; prepared to strike down their fiendish harassers.