Hey there! Love the character and your rendering! It's looking so great! :D The right arm annoyed me a bit. The whole arm was a bit too separated from the rib cage, and the pose of it was a bit uncomfortable. Mimic the pose and you'll see that it feels more natural if the upper arm points backward. On the other hand, sorry for the bad painting, but I wanted to push the shadows and lighting. I also painted the BG with a neutral gray to have better control of the values. I painted some cyans in the sword since it was hard to see it at first, this way I believe it helps to stand out more, or you can see if paint a whole cyan metal with some small goldish patterns. You need to make it stand out since it's the main weapon of the character. Think about adding a bit of storytelling, like some scars or something that helps to communicate a bit of context of who this guy is. Hope this helps!
