I don't have a problem with anyone copying my art for their own enjoyment, as fanart, or for educational purposes or does not acknowledge where the original came from. When someone seeks to profit from the copied art and /or denies it's a swipe is when I react.
At first I just posted a comment on his page asking if he had used reference for his drawing. The he removed my message and blocked me so I contacted DA and filed a greivance sending them the drawings I've posted below.
It evidently worked because a few hours later I received an e-mail from him telling me that he removed the art, but still denied that he had copied it.
So, thank you Wren.
The top drawing is mine (obviously), the next drawing is the swipe and the third drawing is the mine laid on top of his - after I flopped it (the one change he made to the art other than changing the characters)